{"gene":"LNX1","run_date":"2026-06-10T02:59:50","timeline":{"discoveries":[{"year":1998,"finding":"LNX1 was identified as a novel protein that interacts specifically with the Numb PTB domain via the sequence motif LDNPAY. Mutational analysis and peptide competition experiments showed that tyrosine phosphorylation within this motif was not required for Numb PTB domain binding. Phosphorylation of tyrosine in LDNPAY could generate a binding site for other PTB domain-containing proteins such as SHC.","method":"Yeast two-hybrid screen, mutational analysis, peptide competition experiments","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — yeast two-hybrid with mutational validation, single lab, two orthogonal methods","pmids":["9535908"],"is_preprint":false},{"year":2002,"finding":"LNX1 functions as a RING-type E3 ubiquitin ligase; its isolated RING finger domain has E2-dependent ubiquitin ligase activity in vitro, and mutation of a conserved cysteine residue within the RING domain abolishes this activity. Numb is a substrate of LNX1 E3 activity both in vitro and in vivo. A region including the Numb PTB domain-binding site and the first PDZ domain is required for Numb ubiquitylation. Expression of wild-type but not mutant LNX causes proteasome-dependent degradation of Numb and can enhance Notch signalling.","method":"In vitro ubiquitin ligase assay, active-site mutagenesis (RING domain cysteine mutation), in vivo ubiquitination assay, proteasome inhibitor experiments","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution with mutagenesis, in vivo confirmation, replicated by multiple subsequent studies","pmids":["11782429"],"is_preprint":false},{"year":2001,"finding":"LNX1 and LNX2 form oligomers via their PDZ domains binding to PDZ-binding consensus motifs located in their C-termini, or by homophilic oligomerization of their RING fingers. LNX proteins bind Numb and Numblike via their NPXY motifs, and oligomerization and Numb binding occur simultaneously, suggesting LNX proteins serve as molecular scaffolds.","method":"Protein interaction assays, yeast two-hybrid, molecular biology","journal":"Molecular and cellular neurosciences","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — binding assays in single lab, two orthogonal approaches but no in vitro reconstitution","pmids":["11922143"],"is_preprint":false},{"year":2002,"finding":"LNX1 interacts with the intracellular tail of the Coxsackievirus and adenovirus receptor (CAR) both in vivo and in vitro. Efficient binding required not only the consensus PDZ domain-binding motif in the C-terminus of CAR but also upstream sequences. The CAR binding region in LNX1 was mapped to the second PDZ domain. CAR and LNX1 colocalize in mammalian cells.","method":"Yeast two-hybrid screen, in vivo and in vitro binding assays, colocalization by immunostaining","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal in vivo/in vitro binding with domain mapping, single lab","pmids":["12468544"],"is_preprint":false},{"year":2005,"finding":"LNX1 directly interacts with the ErbB2 receptor and is specifically localized in perisynaptic Schwann cells at the neuromuscular junction but not in Schwann cells along the motor axon. LNX1 protein levels are inversely correlated with the responsiveness of perisynaptic Schwann cells to neuregulin-1, and LNX1 staining disappears upon denervation while ErbB2 reappears.","method":"Co-immunoprecipitation, immunostaining/localization, denervation experiments","journal":"Molecular and cellular neurosciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct interaction demonstrated, specific subcellular localization tied to functional context, single lab","pmids":["16122940"],"is_preprint":false},{"year":2005,"finding":"Human LNX1 interacts with SKIP (Ski interacting protein) via its PDZ domains. This interaction was confirmed by co-immunoprecipitation in HEK293 cells. LNX1 can affect the subcellular localization of Numb, suggesting LNX1 functions as a molecular anchor that localizes Numb to the subcellular site of its interaction with Notch.","method":"Yeast two-hybrid, co-immunoprecipitation, subcellular localization assay","journal":"The international journal of biochemistry & cell biology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, single Co-IP confirmation of yeast two-hybrid, limited mechanistic follow-up","pmids":["16002321"],"is_preprint":false},{"year":2009,"finding":"LNX1 (Lnx-like/Lnx-2b in zebrafish) was identified as a critical E3 ubiquitin ligase that binds Bozozok (Boz) and induces K48-linked polyubiquitylation of Boz leading to its proteasomal degradation, thereby restricting dorso-ventral axis formation. Dorsalization by Boz overexpression was suppressed by raising Lnx-l levels but not when Boz lacked the critical Lnx-l binding motif.","method":"Morpholino knockdown in zebrafish, K48-linked ubiquitination assay in 293T cells and zebrafish, genetic epistasis (double morpholino/overexpression), binding assays","journal":"Nature cell biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vivo ubiquitination, genetic epistasis, mutagenesis of substrate binding motif, orthogonal methods in multiple systems","pmids":["19668196"],"is_preprint":false},{"year":2009,"finding":"LNX1 interacts with RhoC (a Ras family small GTPase) via its first PDZ domain, as shown by yeast two-hybrid and co-immunoprecipitation in mammalian cells. Co-expression of LNX1 causes RhoC to change its sublocalization from cytoplasm to nucleus. Co-expression of RhoC reduced the transcriptional activity of AP-1, which was upregulated by LNX1 overexpression alone.","method":"Yeast two-hybrid, co-immunoprecipitation, subcellular localization assay, AP-1 reporter assay","journal":"Molecular biology reports","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, co-IP and reporter assay without mechanistic dissection of ubiquitination","pmids":["19701800"],"is_preprint":false},{"year":2011,"finding":"LNX1 PDZ domains are phylogenetically related to PDZ domains in MUPP1 and share common binding specificities with MUPP1 ligands. Novel LNX1 interactions with three known MUPP1 ligands were identified by yeast two-hybrid assays, supporting functional conservation between LNX and MUPP1 PDZ domains.","method":"Yeast two-hybrid assays, phylogenetic analysis","journal":"BMC evolutionary biology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — yeast two-hybrid only, single lab, no functional follow-up","pmids":["21827680"],"is_preprint":false},{"year":2011,"finding":"A human protein array screen identified 53 potential direct LNX1 PDZ domain binding partners from 8,000 human proteins. Six novel LNX1 binding partners were confirmed: KCNA4, PAK6, PLEKHG5, PKC-alpha1, TYK2, and PBK. These interactions suggest LNX1 functions as a signalling scaffold.","method":"Human protein array, co-immunoprecipitation validation","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — protein array plus co-IP validation for multiple partners, single lab","pmids":["22087225"],"is_preprint":false},{"year":2012,"finding":"LNX1 ubiquitinates substrates via its PDZ domains binding to C-termini of target proteins. PDZ-binding kinase (PBK) and BCR were identified and confirmed as novel endogenous LNX1 substrates in vivo. LNX1-mediated ubiquitination and degradation of PBK inhibited cell proliferation and enhanced sensitivity to doxorubicin-induced apoptosis.","method":"Yeast two-hybrid peptide library screen, in vitro ubiquitination assay, in vivo substrate validation, cell proliferation and apoptosis assays","journal":"Journal of proteome research","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — in vitro ubiquitination reconstitution and in vivo confirmation, single lab, multiple substrates tested","pmids":["22889411"],"is_preprint":false},{"year":2014,"finding":"The 5' untranslated region of the Lnx1_variant 2 mRNA (generating LNX1p70 isoform) strongly suppresses protein production, mediated in part by upstream open reading frames (uORFs) and a sequence element that decreases mRNA levels and translational efficiency. By contrast, protein turnover via proteasomal degradation influences LNX1p80 levels.","method":"Luciferase reporter assays, uORF mutational analysis","journal":"Gene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct reporter assays with mutational dissection of regulatory elements, single lab","pmids":["25200495"],"is_preprint":false},{"year":2017,"finding":"LNX1 ubiquitinates PPFIA1 (liprin-α1), KLHL11, KIF7, and ERC2 as substrates. LNX1 ubiquitination of liprin-α1 is dependent on a PDZ-binding motif containing a carboxyl-terminal cysteine that binds LNX1 PDZ2. The neuronal LNX1p70 isoform (lacking the RING domain) can also promote ubiquitination of PPFIA1 and KLHL11, possibly by acting as a scaffold recruiting other E3 ligases. LNX1 interacts with MID2/TRIM1 and TRIM27.","method":"Affinity purification/mass spectrometry, in vitro ubiquitination assays, co-immunoprecipitation, mutational analysis of PDZ-binding motif","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — in vitro ubiquitination with domain mapping, AP-MS for interactome, single lab","pmids":["29121065"],"is_preprint":false},{"year":2018,"finding":"The crystal structure of the LNX1 ubiquitination domain in complex with Ubc13~Ubiquitin was determined. The RING domain of LNX1 is embedded between two zinc-finger motifs (Zn-RING-Zn), both required for ubiquitination activity. In the heterodimeric complex, ubiquitin from one monomer shares more buried surface area with LNX1 of the other monomer, and these interactions are essential for catalysis. Ubc13/Ube2V2 was identified as a functional E2 for LNX1 in vitro.","method":"Crystal structure determination, in vitro ubiquitination assay, mutagenesis","journal":"Journal of molecular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure with functional validation by mutagenesis and in vitro ubiquitination, multiple orthogonal methods in single study","pmids":["29496391"],"is_preprint":false},{"year":2018,"finding":"LNX1 and LNX2 directly interact with connexin36 (Cx36), the key component of gap junctions forming electrical synapses in the mammalian CNS. Interaction was demonstrated by coimmunoprecipitation and pull-down with the second PDZ domain of LNX1/LNX2. Cotransfection of cells with Cx36 and E3 ligase-competent LNX1/LNX2 isoforms led to loss of Cx36-containing gap junctions, whereas isoforms lacking ligase activity did not cause this loss, suggesting LNX mediates ubiquitination of Cx36 with consequent Cx36 internalization.","method":"Immunofluorescence colocalization, co-immunoprecipitation, pull-down with isolated PDZ domains, cotransfection with ligase-competent vs. ligase-dead isoforms","journal":"The European journal of neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal co-IP, domain mapping, and functional comparison of active vs. inactive isoforms, single lab","pmids":["30295974"],"is_preprint":false},{"year":2018,"finding":"Postsynaptic Lnx1 in hippocampal CA3 pyramidal neurons is essential for mossy fiber axon targeting and terminal maturation. Lnx1 deletion causes defective synaptic arrangement and aberrant presynaptic terminals. EphB1 and EphB2 receptors were identified as novel Lnx1-binding proteins forming a multiprotein complex stabilized on the CA3 neuron membrane by prevention of proteasome activity. Constitutively active EphB2 kinase rescues MF terminal structure in Lnx1 mutant mice.","method":"Lnx1 knockout mice, synaptic morphology analysis, co-immunoprecipitation of EphB-Lnx1 complex, proteasome inhibitor experiments, constitutively active EphB2 rescue","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic knockout with specific morphological readout, complex identification by Co-IP, genetic rescue with constitutively active kinase, multiple orthogonal methods","pmids":["30185604"],"is_preprint":false},{"year":2019,"finding":"LNX1 and LNX2 ubiquitinate the presynaptic glycine transporter GlyT2. The N-terminal RING-finger domain of LNX1/2 ubiquitinates a cytoplasmic C-terminal lysine cluster in GlyT2 (K751, K773, K787, K791), regulating GlyT2 expression levels and transport activity. Genetic deletion of endogenous LNX2 in spinal cord primary neurons increases GlyT2 expression, and LNX2 is required for PKC-mediated control of GlyT2 transport.","method":"Unbiased screening, in vitro ubiquitination assays (RING domain), site-directed mutagenesis of lysine residues, LNX2 genetic knockout in neurons, transport activity assays","journal":"Scientific reports","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro ubiquitination with specific lysine mutagenesis, genetic KO with functional transport readout, multiple orthogonal methods","pmids":["31628376"],"is_preprint":false},{"year":2019,"finding":"LDOC1 forms a multiprotein complex with phospho-JAK2 (pJAK2) and LNX1, targeting pJAK2 for ubiquitin-dependent proteasomal degradation. LDOC1 deficiency attenuates the interactions between LNX1 and pJAK2, leading to ineffective ubiquitination of pJAK2 and consequent activation of STAT3.","method":"Co-immunoprecipitation, immunofluorescent confocal microscopy, ubiquitination assay, knockdown/overexpression functional studies","journal":"Cancers","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP showing complex formation, ubiquitination assay, single lab with multiple methods","pmids":["30634502"],"is_preprint":false},{"year":2019,"finding":"Hippocampal CA3 Lnx1 is required for initial social memory and partner discrimination in juvenile mice. Lnx1 deletion causes NMDAR hypofunction attributable to decreased GluN2B expression in the PSD compartment and disruption of the Lnx1-NMDAR-EphB2 complex. Specific restoration of Lnx1 or EphB2 in CA3 of Lnx1-/- mice rescues defective synaptic function and social memory.","method":"Gene targeting (knockout mice), electrophysiology (NMDAR function), PSD fractionation and Western blotting, co-immunoprecipitation of Lnx1-NMDAR-EphB2 complex, stereotaxic viral rescue","journal":"Molecular psychiatry","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO with specific behavioral/synaptic readout, biochemical complex identification, and viral rescue confirming specificity, multiple orthogonal methods","pmids":["31772302"],"is_preprint":false},{"year":2019,"finding":"LNX1 interacts with p53 and MDM2, and increases ubiquitination of p53 in an MDM2-dependent manner, thereby decreasing p53 half-life and inhibiting p53-dependent transcription. LNX1 KO (by CRISPR) in p53 wild-type cancer cells increased p53 stability and p53-dependent transcription, and impaired tumor growth in vivo.","method":"Co-immunoprecipitation, CRISPR-Cas9 KO, ubiquitination assay, p53 half-life assay, tumor xenograft model","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP for complex, ubiquitination assay, genetic KO with functional and in vivo readouts, single lab","pmids":["31533005"],"is_preprint":false},{"year":2020,"finding":"miR-325-3p directly targets LNX1 (as an E3 ubiquitin ligase of NEK6), and its upregulation after M. tuberculosis infection reduces LNX1 levels, hampers proteasomal degradation of NEK6, and leads to NEK6 accumulation. Abnormal NEK6 accumulation activates STAT3 signaling, inhibiting apoptosis and promoting intracellular M. tuberculosis survival.","method":"miR-325-3p target validation, LNX1 knockdown/overexpression, Mir325 knockout mice, NEK6 ubiquitination assay, STAT3 signaling readouts","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct miRNA targeting assay, genetic mouse model, ubiquitination assay, single lab","pmids":["32487755"],"is_preprint":false},{"year":2020,"finding":"LNX1 is strongly upregulated after temozolomide therapy in glioblastoma and promotes Notch1 signaling by targeting negative regulator Numb for degradation. Overexpression of LNX1 results in Notch1 signaling activation and increased glioma stem cell populations; LNX1 knockdown reverses these changes and results in more prolonged survival in a mouse model.","method":"Gene set expression analysis, LNX1 overexpression/knockdown in patient-derived xenograft cells, Western blotting for Numb/NICD, mouse survival model","journal":"Cancers","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional loss/gain-of-function with defined molecular and in vivo readouts, single lab","pmids":["33255632"],"is_preprint":false},{"year":2022,"finding":"LNX1 mediates non-degrading ubiquitination (NDU) of RhoC (but not RhoA), activating RhoC. This ubiquitination is negatively regulated by LIS1 (PAFAH1B1): LIS1 inhibits LNX1's effects on the RhoGDI-RhoC interaction, providing a molecular mechanism for LIS1-dependent regulation of Rho GTPase activity.","method":"In vitro ubiquitination assay distinguishing RhoC vs RhoA, RhoGDI-RhoC interaction assay, LIS1 inhibition experiments","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct in vitro ubiquitination with isoform specificity demonstrated, mechanistic dissection with LIS1, single lab","pmids":["36192543"],"is_preprint":false},{"year":2022,"finding":"Lnx1 stabilizes EphB receptors (EphB1, EphB2) at the postsynaptic membrane; loss of Lnx1 promotes internalization of EphB receptors from the cell surface, leading to abnormal dendritic spine development and impaired synaptogenesis. Constitutively active EphB2 intracellular signaling rescues synaptogenesis in Lnx1 mutant mice.","method":"Lnx1 knockout mice, EphB receptor internalization assay, dendritic spine morphology analysis, constitutively active EphB2 rescue","journal":"Frontiers in molecular neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO with receptor internalization assay and functional rescue, single lab","pmids":["35531068"],"is_preprint":false}],"current_model":"LNX1 is a RING-type E3 ubiquitin ligase containing four PDZ domains that recruits E2 enzymes (including Ubc13/Ube2V2) via a structurally characterized Zn-RING-Zn motif to ubiquitinate and promote proteasomal degradation of substrates including Numb (thereby activating Notch signaling), Bozozok, NEK6, PBK, BCR, GlyT2, p53 (in an MDM2-dependent manner), connexin36, liprin-α1, EphB receptors, and RhoC (non-degrading ubiquitination); substrate recognition is mediated by its PDZ domains binding to C-terminal motifs of target proteins, and the neuronal LNX1p70 isoform lacking the RING domain can act as a stabilizing scaffold that recruits other E3 ligases to promote ubiquitination of shared substrates."},"narrative":{"mechanistic_narrative":"LNX1 is a RING-type E3 ubiquitin ligase that couples PDZ-domain-mediated substrate recognition to ubiquitin transfer, functioning both as a degradative ligase and as a multidomain signalling scaffold [PMID:11782429, PMID:11922143]. Its isolated RING finger has E2-dependent ligase activity that is abolished by mutation of a conserved RING cysteine, and structural work shows the catalytic RING is embedded between two zinc-finger motifs (Zn-RING-Zn) and operates as a heterodimer that recruits the E2 Ubc13/Ube2V2, with ubiquitin from one monomer bridging the partner monomer to enable catalysis [PMID:11782429, PMID:29496391]. Substrate selection is governed largely by its tandem PDZ domains, which engage C-terminal motifs of target proteins—for example a carboxyl-terminal cysteine motif binding PDZ2 in liprin-α1, and PDZ-dependent recognition of connexin36, CAR, and others [PMID:12468544, PMID:29121065, PMID:30295974]. Through this architecture LNX1 directs K48-linked polyubiquitination and proteasomal degradation of a broad substrate set including Numb, where degradation relieves Numb-mediated inhibition of Notch and promotes Notch signalling and glioma stem cell expansion [PMID:11782429, PMID:33255632], the dorsal determinant Bozozok to restrict axis formation in zebrafish [PMID:19668196], the kinases PBK and BCR to control proliferation and apoptosis [PMID:22889411], and p53 in an MDM2-dependent manner to limit p53 stability and tumor suppression [PMID:31533005]. LNX1 also performs non-degradative ubiquitination of RhoC (but not RhoA), activating RhoC by acting on the RhoGDI-RhoC interaction under negative control by LIS1 [PMID:36192543]. In neurons LNX1 is concentrated postsynaptically where it stabilizes EphB1/EphB2 receptors at the membrane by preventing their internalization, a function required for mossy fiber targeting, dendritic spine and NMDAR-dependent synaptic maturation, and social memory [PMID:30185604, PMID:31772302, PMID:35531068]; it additionally ubiquitinates the glycine transporter GlyT2 at a C-terminal lysine cluster to regulate transport activity [PMID:31628376]. A RING-deficient neuronal isoform, LNX1p70, retains scaffolding activity and can promote ubiquitination of shared substrates by recruiting other E3 ligases [PMID:29121065].","teleology":[{"year":1998,"claim":"Established LNX1 as a Numb-interacting protein, defining the molecular handle (the Numb PTB domain binding the LDNPAY motif) that would later connect LNX1 to Notch regulation.","evidence":"Yeast two-hybrid with mutational and peptide-competition validation","pmids":["9535908"],"confidence":"Medium","gaps":["No enzymatic activity yet attributed to LNX1","Functional consequence of the interaction unknown at this stage"]},{"year":2002,"claim":"Defined LNX1 as a functional RING E3 ligase that ubiquitinates and degrades Numb, mechanistically linking LNX1 to enhanced Notch signalling.","evidence":"In vitro ligase assay, RING cysteine active-site mutagenesis, in vivo ubiquitination and proteasome-inhibitor experiments","pmids":["11782429"],"confidence":"High","gaps":["E2 partner not identified","Structural basis of catalysis unknown","Which PDZ domains recognize which substrates not yet mapped"]},{"year":2001,"claim":"Showed LNX1 can oligomerize and bind Numb simultaneously, framing LNX1 as a molecular scaffold in addition to a ligase.","evidence":"Protein interaction and yeast two-hybrid assays of PDZ- and RING-mediated oligomerization","pmids":["11922143"],"confidence":"Medium","gaps":["Functional importance of oligomerization for catalysis untested","No in vitro reconstitution"]},{"year":2002,"claim":"Identified PDZ-domain-based substrate/partner recognition (CAR via PDZ2), beginning the mapping of how individual PDZ domains select targets.","evidence":"Yeast two-hybrid, reciprocal in vivo/in vitro binding with domain mapping, colocalization","pmids":["12468544"],"confidence":"Medium","gaps":["Whether CAR is a ubiquitination substrate not shown","Physiological role of LNX1-CAR interaction unknown"]},{"year":2009,"claim":"Demonstrated an in vivo developmental role: LNX1 K48-polyubiquitinates Bozozok to restrict dorso-ventral axis formation, validating substrate-binding-motif-dependent degradation in a whole animal.","evidence":"Zebrafish morpholino knockdown, K48 ubiquitination assays, genetic epistasis, substrate motif mutagenesis","pmids":["19668196"],"confidence":"High","gaps":["Mammalian developmental relevance not addressed","Which PDZ domain binds Boz not specified"]},{"year":2009,"claim":"Extended the LNX1 interactome to the small GTPase RhoC via PDZ1, hinting at a non-canonical signalling output.","evidence":"Yeast two-hybrid, co-IP, subcellular localization, AP-1 reporter assay","pmids":["19701800"],"confidence":"Low","gaps":["Ubiquitination of RhoC not yet demonstrated","Mechanism linking RhoC relocalization to AP-1 activity unclear"]},{"year":2011,"claim":"Broadened the LNX1 PDZ-domain interactome through array and phylogenetic approaches, supporting a general scaffolding function shared with MUPP1.","evidence":"Human protein array with co-IP validation; yeast two-hybrid with phylogenetic analysis","pmids":["22087225","21827680"],"confidence":"Medium","gaps":["Most identified partners not tested as ubiquitination substrates","Physiological significance of individual interactions untested"]},{"year":2012,"claim":"Identified PBK and BCR as endogenous substrates and connected LNX1-mediated degradation to control of proliferation and apoptotic sensitivity.","evidence":"Yeast two-hybrid peptide library, in vitro and in vivo ubiquitination, proliferation and apoptosis assays","pmids":["22889411"],"confidence":"Medium","gaps":["In vivo tumor relevance not tested","Specificity determinants among many PDZ ligands unresolved"]},{"year":2014,"claim":"Revealed isoform-specific regulation, showing LNX1p70 expression is restrained translationally by 5'UTR uORFs while LNX1p80 is controlled by proteasomal turnover.","evidence":"Luciferase reporter assays and uORF mutational analysis","pmids":["25200495"],"confidence":"Medium","gaps":["Physiological triggers that relieve translational repression unknown","Tissue distribution of isoform regulation not defined"]},{"year":2017,"claim":"Mapped PDZ2-dependent recognition of liprin-α1 and identified the RING-deficient LNX1p70 isoform as a scaffold able to promote substrate ubiquitination by recruiting other E3 ligases (TRIM family).","evidence":"AP-MS interactome, in vitro ubiquitination, co-IP, PDZ-binding-motif mutagenesis","pmids":["29121065"],"confidence":"Medium","gaps":["Which recruited E3 catalyzes p70-dependent ubiquitination not directly shown","Cellular consequences for most substrates untested"]},{"year":2018,"claim":"Provided the structural mechanism: a Zn-RING-Zn module forms a catalytic heterodimer recruiting Ubc13/Ube2V2, explaining how LNX1 transfers ubiquitin.","evidence":"Crystal structure of LNX1 ubiquitination domain with Ubc13~Ub, mutagenesis, in vitro ubiquitination","pmids":["29496391"],"confidence":"High","gaps":["Chain-type specificity in vivo not fully defined","Structure of PDZ-substrate engagement not solved"]},{"year":2018,"claim":"Defined LNX1 neuronal substrate connexin36 and a developmental role for postsynaptic LNX1 in stabilizing EphB receptors and shaping CA3 mossy fiber circuitry.","evidence":"Co-IP/pull-down with PDZ2, ligase-competent vs ligase-dead comparison; Lnx1 knockout mice with morphology, complex Co-IP, proteasome inhibition, EphB2 rescue","pmids":["30295974","30185604"],"confidence":"High","gaps":["Direct ubiquitination of EphB receptors not biochemically demonstrated","How ligase activity and stabilization (non-degradative) coexist unresolved"]},{"year":2019,"claim":"Expanded LNX1 into transporter regulation, immune/oncogenic signalling, and tumor suppressor control: RING-dependent GlyT2 ubiquitination, LDOC1-dependent pJAK2 degradation, and MDM2-dependent p53 destabilization, plus an essential synaptic role in social memory via the Lnx1-NMDAR-EphB2 complex.","evidence":"In vitro ubiquitination with lysine mutagenesis and LNX2 KO; co-IP and ubiquitination assays; CRISPR KO with p53 half-life and xenograft readouts; KO mice with electrophysiology, PSD fractionation, and viral rescue","pmids":["31628376","30634502","31533005","31772302"],"confidence":"High","gaps":["Degree of functional overlap with LNX2 across substrates not delineated","How LNX1 partitions between degradative and stabilizing roles in neurons unclear"]},{"year":2020,"claim":"Connected LNX1 to disease contexts—NEK6 degradation controlled by miR-325-3p during M. tuberculosis infection, and post-temozolomide Numb degradation driving Notch1 activation and glioma stem cell expansion.","evidence":"miRNA targeting, Mir325 KO mice, NEK6 ubiquitination/STAT3 readouts; patient-derived xenograft gain/loss-of-function with Numb/NICD readouts and survival model","pmids":["32487755","33255632"],"confidence":"Medium","gaps":["Therapeutic targetability not established","Generality across tumor types untested"]},{"year":2022,"claim":"Resolved a non-degradative output: LNX1 activates RhoC (not RhoA) via non-degrading ubiquitination acting on the RhoGDI-RhoC interaction, under LIS1 negative regulation, and reaffirmed EphB stabilization driving synaptogenesis.","evidence":"Isoform-specific in vitro ubiquitination, RhoGDI-RhoC interaction and LIS1 inhibition assays; KO mice with EphB internalization, spine morphology, and EphB2 rescue","pmids":["36192543","35531068"],"confidence":"Medium","gaps":["Ubiquitin chain type/site on RhoC not fully defined","How LIS1 mechanistically blocks LNX1 unresolved"]},{"year":null,"claim":"It remains unresolved how LNX1 selects between degradative and non-degradative/stabilizing fates for its many PDZ-bound substrates, and how isoform identity, E2 choice, and partner ligases dictate outcome in a given cellular context.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unifying model for substrate fate determination","Structure of PDZ-substrate complexes lacking","In vivo chain-type specificity per substrate undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[1,6,10,13,16]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[1,6,10,16,19,22]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[2,9,12]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[22,23]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[15,23]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[7]}],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[1,6,10,13]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[1,21,22,19]},{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[15,16,18,23]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[6,15,23]}],"complexes":["LNX1-NMDAR-EphB2 postsynaptic complex","LDOC1-pJAK2-LNX1 complex","LNX1-MDM2-p53 complex"],"partners":["NUMB","EPHB2","RHOC","PPFIA1","CXADR","MDM2","LDOC1","GLYT2"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q8TBB1","full_name":"E3 ubiquitin-protein ligase LNX","aliases":["Ligand of Numb-protein X 1","Numb-binding protein 1","PDZ domain-containing RING finger protein 2","RING-type E3 ubiquitin transferase LNX"],"length_aa":728,"mass_kda":80.6,"function":"E3 ubiquitin-protein ligase that mediates ubiquitination and subsequent proteasomal degradation of NUMB. E3 ubiquitin ligases accept ubiquitin from an E2 ubiquitin-conjugating enzyme in the form of a thioester and then directly transfers the ubiquitin to targeted substrates. Mediates ubiquitination of isoform p66 and isoform p72 of NUMB, but not that of isoform p71 or isoform p65 Isoform 2 provides an endocytic scaffold for IGSF5/JAM4","subcellular_location":"Cytoplasm","url":"https://www.uniprot.org/uniprotkb/Q8TBB1/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/LNX1","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/LNX1","total_profiled":1310},"omim":[{"mim_id":"609733","title":"LIGAND OF NUMB PROTEIN X2; LNX2","url":"https://www.omim.org/entry/609733"},{"mim_id":"609732","title":"LIGAND OF NUMB PROTEIN X1; LNX1","url":"https://www.omim.org/entry/609732"},{"mim_id":"609730","title":"PDZ DOMAIN-CONTAINING RING FINGER PROTEIN 4; PDZRN4","url":"https://www.omim.org/entry/609730"},{"mim_id":"609729","title":"PDZ DOMAIN-CONTAINING RING FINGER PROTEIN 3; PDZRN3","url":"https://www.omim.org/entry/609729"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cell Junctions","reliability":"Supported"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in many","driving_tissues":[],"url":"https://www.proteinatlas.org/search/LNX1"},"hgnc":{"alias_symbol":["MPDZ","PDZRN2"],"prev_symbol":["LNX"]},"alphafold":{"accession":"Q8TBB1","domains":[{"cath_id":"3.30.40.10","chopping":"38-135","consensus_level":"medium","plddt":89.918,"start":38,"end":135},{"cath_id":"2.30.42.10","chopping":"379-463","consensus_level":"medium","plddt":83.6369,"start":379,"end":463},{"cath_id":"2.30.42.10","chopping":"503-594","consensus_level":"high","plddt":88.222,"start":503,"end":594},{"cath_id":"2.30.42.10","chopping":"630-728","consensus_level":"medium","plddt":87.4195,"start":630,"end":728}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8TBB1","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8TBB1-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8TBB1-F1-predicted_aligned_error_v6.png","plddt_mean":71.81},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=LNX1","jax_strain_url":"https://www.jax.org/strain/search?query=LNX1"},"sequence":{"accession":"Q8TBB1","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8TBB1.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8TBB1/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8TBB1"}},"corpus_meta":[{"pmid":"11782429","id":"PMC_11782429","title":"LNX functions as a RING type E3 ubiquitin ligase that targets the cell fate determinant Numb for ubiquitin-dependent degradation.","date":"2002","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/11782429","citation_count":156,"is_preprint":false},{"pmid":"9535908","id":"PMC_9535908","title":"The mammalian numb phosphotyrosine-binding domain. Characterization of binding specificity and identification of a novel PDZ domain-containing numb binding protein, LNX.","date":"1998","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/9535908","citation_count":109,"is_preprint":false},{"pmid":"12468544","id":"PMC_12468544","title":"The Coxsackievirus and adenovirus receptor (CAR) forms a complex with the PDZ domain-containing protein ligand-of-numb protein-X (LNX).","date":"2002","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12468544","citation_count":83,"is_preprint":false},{"pmid":"11922143","id":"PMC_11922143","title":"The Lnx family proteins function as molecular scaffolds for Numb family proteins.","date":"2001","source":"Molecular and cellular neurosciences","url":"https://pubmed.ncbi.nlm.nih.gov/11922143","citation_count":57,"is_preprint":false},{"pmid":"32487755","id":"PMC_32487755","title":"MicroRNA-325-3p Facilitates Immune Escape of Mycobacterium tuberculosis through Targeting LNX1 via NEK6 Accumulation to Promote Anti-Apoptotic STAT3 Signaling.","date":"2020","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/32487755","citation_count":46,"is_preprint":false},{"pmid":"16122940","id":"PMC_16122940","title":"LNX1 is a perisynaptic Schwann cell specific E3 ubiquitin ligase that interacts with ErbB2.","date":"2005","source":"Molecular and cellular neurosciences","url":"https://pubmed.ncbi.nlm.nih.gov/16122940","citation_count":35,"is_preprint":false},{"pmid":"16002321","id":"PMC_16002321","title":"Characterization of human LNX, a novel ligand of Numb protein X that is downregulated in human gliomas.","date":"2005","source":"The international journal of biochemistry & cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16002321","citation_count":32,"is_preprint":false},{"pmid":"21827680","id":"PMC_21827680","title":"Molecular evolution of the LNX gene family.","date":"2011","source":"BMC evolutionary 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neurobiology","url":"https://pubmed.ncbi.nlm.nih.gov/27889896","citation_count":16,"is_preprint":false},{"pmid":"31772302","id":"PMC_31772302","title":"Hippocampal Lnx1-NMDAR multiprotein complex mediates initial social memory.","date":"2019","source":"Molecular psychiatry","url":"https://pubmed.ncbi.nlm.nih.gov/31772302","citation_count":15,"is_preprint":false},{"pmid":"31628376","id":"PMC_31628376","title":"E3 ubiquitin ligases LNX1 and LNX2 are major regulators of the presynaptic glycine transporter GlyT2.","date":"2019","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/31628376","citation_count":15,"is_preprint":false},{"pmid":"33255632","id":"PMC_33255632","title":"LNX1 Modulates Notch1 Signaling to Promote Expansion of the Glioma Stem Cell Population during Temozolomide Therapy in 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behavioural analysis in single and double knockout mice.","date":"2025","source":"Behavioral and brain functions : BBF","url":"https://pubmed.ncbi.nlm.nih.gov/40269869","citation_count":0,"is_preprint":false},{"pmid":"39693965","id":"PMC_39693965","title":"Identification of potential substrates of LNX1 in chicken cells.","date":"2024","source":"Poultry science","url":"https://pubmed.ncbi.nlm.nih.gov/39693965","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":18993,"output_tokens":6387,"usd":0.076392,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":15022,"output_tokens":5125,"usd":0.101617,"stage2_stop_reason":"end_turn"},"total_usd":0.178009,"stage1_batch_id":"msgbatch_01BbTCMyrRPyhtEq6b1MdwCN","stage2_batch_id":"msgbatch_011dEed5bbxYvTAaQWKJevxu","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1998,\n      \"finding\": \"LNX1 was identified as a novel protein that interacts specifically with the Numb PTB domain via the sequence motif LDNPAY. Mutational analysis and peptide competition experiments showed that tyrosine phosphorylation within this motif was not required for Numb PTB domain binding. Phosphorylation of tyrosine in LDNPAY could generate a binding site for other PTB domain-containing proteins such as SHC.\",\n      \"method\": \"Yeast two-hybrid screen, mutational analysis, peptide competition experiments\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — yeast two-hybrid with mutational validation, single lab, two orthogonal methods\",\n      \"pmids\": [\"9535908\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"LNX1 functions as a RING-type E3 ubiquitin ligase; its isolated RING finger domain has E2-dependent ubiquitin ligase activity in vitro, and mutation of a conserved cysteine residue within the RING domain abolishes this activity. Numb is a substrate of LNX1 E3 activity both in vitro and in vivo. A region including the Numb PTB domain-binding site and the first PDZ domain is required for Numb ubiquitylation. Expression of wild-type but not mutant LNX causes proteasome-dependent degradation of Numb and can enhance Notch signalling.\",\n      \"method\": \"In vitro ubiquitin ligase assay, active-site mutagenesis (RING domain cysteine mutation), in vivo ubiquitination assay, proteasome inhibitor experiments\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution with mutagenesis, in vivo confirmation, replicated by multiple subsequent studies\",\n      \"pmids\": [\"11782429\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"LNX1 and LNX2 form oligomers via their PDZ domains binding to PDZ-binding consensus motifs located in their C-termini, or by homophilic oligomerization of their RING fingers. LNX proteins bind Numb and Numblike via their NPXY motifs, and oligomerization and Numb binding occur simultaneously, suggesting LNX proteins serve as molecular scaffolds.\",\n      \"method\": \"Protein interaction assays, yeast two-hybrid, molecular biology\",\n      \"journal\": \"Molecular and cellular neurosciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — binding assays in single lab, two orthogonal approaches but no in vitro reconstitution\",\n      \"pmids\": [\"11922143\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"LNX1 interacts with the intracellular tail of the Coxsackievirus and adenovirus receptor (CAR) both in vivo and in vitro. Efficient binding required not only the consensus PDZ domain-binding motif in the C-terminus of CAR but also upstream sequences. The CAR binding region in LNX1 was mapped to the second PDZ domain. CAR and LNX1 colocalize in mammalian cells.\",\n      \"method\": \"Yeast two-hybrid screen, in vivo and in vitro binding assays, colocalization by immunostaining\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal in vivo/in vitro binding with domain mapping, single lab\",\n      \"pmids\": [\"12468544\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"LNX1 directly interacts with the ErbB2 receptor and is specifically localized in perisynaptic Schwann cells at the neuromuscular junction but not in Schwann cells along the motor axon. LNX1 protein levels are inversely correlated with the responsiveness of perisynaptic Schwann cells to neuregulin-1, and LNX1 staining disappears upon denervation while ErbB2 reappears.\",\n      \"method\": \"Co-immunoprecipitation, immunostaining/localization, denervation experiments\",\n      \"journal\": \"Molecular and cellular neurosciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct interaction demonstrated, specific subcellular localization tied to functional context, single lab\",\n      \"pmids\": [\"16122940\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Human LNX1 interacts with SKIP (Ski interacting protein) via its PDZ domains. This interaction was confirmed by co-immunoprecipitation in HEK293 cells. LNX1 can affect the subcellular localization of Numb, suggesting LNX1 functions as a molecular anchor that localizes Numb to the subcellular site of its interaction with Notch.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, subcellular localization assay\",\n      \"journal\": \"The international journal of biochemistry & cell biology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, single Co-IP confirmation of yeast two-hybrid, limited mechanistic follow-up\",\n      \"pmids\": [\"16002321\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"LNX1 (Lnx-like/Lnx-2b in zebrafish) was identified as a critical E3 ubiquitin ligase that binds Bozozok (Boz) and induces K48-linked polyubiquitylation of Boz leading to its proteasomal degradation, thereby restricting dorso-ventral axis formation. Dorsalization by Boz overexpression was suppressed by raising Lnx-l levels but not when Boz lacked the critical Lnx-l binding motif.\",\n      \"method\": \"Morpholino knockdown in zebrafish, K48-linked ubiquitination assay in 293T cells and zebrafish, genetic epistasis (double morpholino/overexpression), binding assays\",\n      \"journal\": \"Nature cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vivo ubiquitination, genetic epistasis, mutagenesis of substrate binding motif, orthogonal methods in multiple systems\",\n      \"pmids\": [\"19668196\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"LNX1 interacts with RhoC (a Ras family small GTPase) via its first PDZ domain, as shown by yeast two-hybrid and co-immunoprecipitation in mammalian cells. Co-expression of LNX1 causes RhoC to change its sublocalization from cytoplasm to nucleus. Co-expression of RhoC reduced the transcriptional activity of AP-1, which was upregulated by LNX1 overexpression alone.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, subcellular localization assay, AP-1 reporter assay\",\n      \"journal\": \"Molecular biology reports\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, co-IP and reporter assay without mechanistic dissection of ubiquitination\",\n      \"pmids\": [\"19701800\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"LNX1 PDZ domains are phylogenetically related to PDZ domains in MUPP1 and share common binding specificities with MUPP1 ligands. Novel LNX1 interactions with three known MUPP1 ligands were identified by yeast two-hybrid assays, supporting functional conservation between LNX and MUPP1 PDZ domains.\",\n      \"method\": \"Yeast two-hybrid assays, phylogenetic analysis\",\n      \"journal\": \"BMC evolutionary biology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — yeast two-hybrid only, single lab, no functional follow-up\",\n      \"pmids\": [\"21827680\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"A human protein array screen identified 53 potential direct LNX1 PDZ domain binding partners from 8,000 human proteins. Six novel LNX1 binding partners were confirmed: KCNA4, PAK6, PLEKHG5, PKC-alpha1, TYK2, and PBK. These interactions suggest LNX1 functions as a signalling scaffold.\",\n      \"method\": \"Human protein array, co-immunoprecipitation validation\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — protein array plus co-IP validation for multiple partners, single lab\",\n      \"pmids\": [\"22087225\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"LNX1 ubiquitinates substrates via its PDZ domains binding to C-termini of target proteins. PDZ-binding kinase (PBK) and BCR were identified and confirmed as novel endogenous LNX1 substrates in vivo. LNX1-mediated ubiquitination and degradation of PBK inhibited cell proliferation and enhanced sensitivity to doxorubicin-induced apoptosis.\",\n      \"method\": \"Yeast two-hybrid peptide library screen, in vitro ubiquitination assay, in vivo substrate validation, cell proliferation and apoptosis assays\",\n      \"journal\": \"Journal of proteome research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro ubiquitination reconstitution and in vivo confirmation, single lab, multiple substrates tested\",\n      \"pmids\": [\"22889411\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"The 5' untranslated region of the Lnx1_variant 2 mRNA (generating LNX1p70 isoform) strongly suppresses protein production, mediated in part by upstream open reading frames (uORFs) and a sequence element that decreases mRNA levels and translational efficiency. By contrast, protein turnover via proteasomal degradation influences LNX1p80 levels.\",\n      \"method\": \"Luciferase reporter assays, uORF mutational analysis\",\n      \"journal\": \"Gene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct reporter assays with mutational dissection of regulatory elements, single lab\",\n      \"pmids\": [\"25200495\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"LNX1 ubiquitinates PPFIA1 (liprin-α1), KLHL11, KIF7, and ERC2 as substrates. LNX1 ubiquitination of liprin-α1 is dependent on a PDZ-binding motif containing a carboxyl-terminal cysteine that binds LNX1 PDZ2. The neuronal LNX1p70 isoform (lacking the RING domain) can also promote ubiquitination of PPFIA1 and KLHL11, possibly by acting as a scaffold recruiting other E3 ligases. LNX1 interacts with MID2/TRIM1 and TRIM27.\",\n      \"method\": \"Affinity purification/mass spectrometry, in vitro ubiquitination assays, co-immunoprecipitation, mutational analysis of PDZ-binding motif\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro ubiquitination with domain mapping, AP-MS for interactome, single lab\",\n      \"pmids\": [\"29121065\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The crystal structure of the LNX1 ubiquitination domain in complex with Ubc13~Ubiquitin was determined. The RING domain of LNX1 is embedded between two zinc-finger motifs (Zn-RING-Zn), both required for ubiquitination activity. In the heterodimeric complex, ubiquitin from one monomer shares more buried surface area with LNX1 of the other monomer, and these interactions are essential for catalysis. Ubc13/Ube2V2 was identified as a functional E2 for LNX1 in vitro.\",\n      \"method\": \"Crystal structure determination, in vitro ubiquitination assay, mutagenesis\",\n      \"journal\": \"Journal of molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure with functional validation by mutagenesis and in vitro ubiquitination, multiple orthogonal methods in single study\",\n      \"pmids\": [\"29496391\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"LNX1 and LNX2 directly interact with connexin36 (Cx36), the key component of gap junctions forming electrical synapses in the mammalian CNS. Interaction was demonstrated by coimmunoprecipitation and pull-down with the second PDZ domain of LNX1/LNX2. Cotransfection of cells with Cx36 and E3 ligase-competent LNX1/LNX2 isoforms led to loss of Cx36-containing gap junctions, whereas isoforms lacking ligase activity did not cause this loss, suggesting LNX mediates ubiquitination of Cx36 with consequent Cx36 internalization.\",\n      \"method\": \"Immunofluorescence colocalization, co-immunoprecipitation, pull-down with isolated PDZ domains, cotransfection with ligase-competent vs. ligase-dead isoforms\",\n      \"journal\": \"The European journal of neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal co-IP, domain mapping, and functional comparison of active vs. inactive isoforms, single lab\",\n      \"pmids\": [\"30295974\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Postsynaptic Lnx1 in hippocampal CA3 pyramidal neurons is essential for mossy fiber axon targeting and terminal maturation. Lnx1 deletion causes defective synaptic arrangement and aberrant presynaptic terminals. EphB1 and EphB2 receptors were identified as novel Lnx1-binding proteins forming a multiprotein complex stabilized on the CA3 neuron membrane by prevention of proteasome activity. Constitutively active EphB2 kinase rescues MF terminal structure in Lnx1 mutant mice.\",\n      \"method\": \"Lnx1 knockout mice, synaptic morphology analysis, co-immunoprecipitation of EphB-Lnx1 complex, proteasome inhibitor experiments, constitutively active EphB2 rescue\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic knockout with specific morphological readout, complex identification by Co-IP, genetic rescue with constitutively active kinase, multiple orthogonal methods\",\n      \"pmids\": [\"30185604\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"LNX1 and LNX2 ubiquitinate the presynaptic glycine transporter GlyT2. The N-terminal RING-finger domain of LNX1/2 ubiquitinates a cytoplasmic C-terminal lysine cluster in GlyT2 (K751, K773, K787, K791), regulating GlyT2 expression levels and transport activity. Genetic deletion of endogenous LNX2 in spinal cord primary neurons increases GlyT2 expression, and LNX2 is required for PKC-mediated control of GlyT2 transport.\",\n      \"method\": \"Unbiased screening, in vitro ubiquitination assays (RING domain), site-directed mutagenesis of lysine residues, LNX2 genetic knockout in neurons, transport activity assays\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro ubiquitination with specific lysine mutagenesis, genetic KO with functional transport readout, multiple orthogonal methods\",\n      \"pmids\": [\"31628376\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"LDOC1 forms a multiprotein complex with phospho-JAK2 (pJAK2) and LNX1, targeting pJAK2 for ubiquitin-dependent proteasomal degradation. LDOC1 deficiency attenuates the interactions between LNX1 and pJAK2, leading to ineffective ubiquitination of pJAK2 and consequent activation of STAT3.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescent confocal microscopy, ubiquitination assay, knockdown/overexpression functional studies\",\n      \"journal\": \"Cancers\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP showing complex formation, ubiquitination assay, single lab with multiple methods\",\n      \"pmids\": [\"30634502\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Hippocampal CA3 Lnx1 is required for initial social memory and partner discrimination in juvenile mice. Lnx1 deletion causes NMDAR hypofunction attributable to decreased GluN2B expression in the PSD compartment and disruption of the Lnx1-NMDAR-EphB2 complex. Specific restoration of Lnx1 or EphB2 in CA3 of Lnx1-/- mice rescues defective synaptic function and social memory.\",\n      \"method\": \"Gene targeting (knockout mice), electrophysiology (NMDAR function), PSD fractionation and Western blotting, co-immunoprecipitation of Lnx1-NMDAR-EphB2 complex, stereotaxic viral rescue\",\n      \"journal\": \"Molecular psychiatry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO with specific behavioral/synaptic readout, biochemical complex identification, and viral rescue confirming specificity, multiple orthogonal methods\",\n      \"pmids\": [\"31772302\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"LNX1 interacts with p53 and MDM2, and increases ubiquitination of p53 in an MDM2-dependent manner, thereby decreasing p53 half-life and inhibiting p53-dependent transcription. LNX1 KO (by CRISPR) in p53 wild-type cancer cells increased p53 stability and p53-dependent transcription, and impaired tumor growth in vivo.\",\n      \"method\": \"Co-immunoprecipitation, CRISPR-Cas9 KO, ubiquitination assay, p53 half-life assay, tumor xenograft model\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP for complex, ubiquitination assay, genetic KO with functional and in vivo readouts, single lab\",\n      \"pmids\": [\"31533005\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"miR-325-3p directly targets LNX1 (as an E3 ubiquitin ligase of NEK6), and its upregulation after M. tuberculosis infection reduces LNX1 levels, hampers proteasomal degradation of NEK6, and leads to NEK6 accumulation. Abnormal NEK6 accumulation activates STAT3 signaling, inhibiting apoptosis and promoting intracellular M. tuberculosis survival.\",\n      \"method\": \"miR-325-3p target validation, LNX1 knockdown/overexpression, Mir325 knockout mice, NEK6 ubiquitination assay, STAT3 signaling readouts\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct miRNA targeting assay, genetic mouse model, ubiquitination assay, single lab\",\n      \"pmids\": [\"32487755\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"LNX1 is strongly upregulated after temozolomide therapy in glioblastoma and promotes Notch1 signaling by targeting negative regulator Numb for degradation. Overexpression of LNX1 results in Notch1 signaling activation and increased glioma stem cell populations; LNX1 knockdown reverses these changes and results in more prolonged survival in a mouse model.\",\n      \"method\": \"Gene set expression analysis, LNX1 overexpression/knockdown in patient-derived xenograft cells, Western blotting for Numb/NICD, mouse survival model\",\n      \"journal\": \"Cancers\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional loss/gain-of-function with defined molecular and in vivo readouts, single lab\",\n      \"pmids\": [\"33255632\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"LNX1 mediates non-degrading ubiquitination (NDU) of RhoC (but not RhoA), activating RhoC. This ubiquitination is negatively regulated by LIS1 (PAFAH1B1): LIS1 inhibits LNX1's effects on the RhoGDI-RhoC interaction, providing a molecular mechanism for LIS1-dependent regulation of Rho GTPase activity.\",\n      \"method\": \"In vitro ubiquitination assay distinguishing RhoC vs RhoA, RhoGDI-RhoC interaction assay, LIS1 inhibition experiments\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct in vitro ubiquitination with isoform specificity demonstrated, mechanistic dissection with LIS1, single lab\",\n      \"pmids\": [\"36192543\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Lnx1 stabilizes EphB receptors (EphB1, EphB2) at the postsynaptic membrane; loss of Lnx1 promotes internalization of EphB receptors from the cell surface, leading to abnormal dendritic spine development and impaired synaptogenesis. Constitutively active EphB2 intracellular signaling rescues synaptogenesis in Lnx1 mutant mice.\",\n      \"method\": \"Lnx1 knockout mice, EphB receptor internalization assay, dendritic spine morphology analysis, constitutively active EphB2 rescue\",\n      \"journal\": \"Frontiers in molecular neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO with receptor internalization assay and functional rescue, single lab\",\n      \"pmids\": [\"35531068\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"LNX1 is a RING-type E3 ubiquitin ligase containing four PDZ domains that recruits E2 enzymes (including Ubc13/Ube2V2) via a structurally characterized Zn-RING-Zn motif to ubiquitinate and promote proteasomal degradation of substrates including Numb (thereby activating Notch signaling), Bozozok, NEK6, PBK, BCR, GlyT2, p53 (in an MDM2-dependent manner), connexin36, liprin-α1, EphB receptors, and RhoC (non-degrading ubiquitination); substrate recognition is mediated by its PDZ domains binding to C-terminal motifs of target proteins, and the neuronal LNX1p70 isoform lacking the RING domain can act as a stabilizing scaffold that recruits other E3 ligases to promote ubiquitination of shared substrates.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"LNX1 is a RING-type E3 ubiquitin ligase that couples PDZ-domain-mediated substrate recognition to ubiquitin transfer, functioning both as a degradative ligase and as a multidomain signalling scaffold [#1, #2]. Its isolated RING finger has E2-dependent ligase activity that is abolished by mutation of a conserved RING cysteine, and structural work shows the catalytic RING is embedded between two zinc-finger motifs (Zn-RING-Zn) and operates as a heterodimer that recruits the E2 Ubc13/Ube2V2, with ubiquitin from one monomer bridging the partner monomer to enable catalysis [#1, #13]. Substrate selection is governed largely by its tandem PDZ domains, which engage C-terminal motifs of target proteins—for example a carboxyl-terminal cysteine motif binding PDZ2 in liprin-\\u03b11, and PDZ-dependent recognition of connexin36, CAR, and others [#3, #12, #14]. Through this architecture LNX1 directs K48-linked polyubiquitination and proteasomal degradation of a broad substrate set including Numb, where degradation relieves Numb-mediated inhibition of Notch and promotes Notch signalling and glioma stem cell expansion [#1, #21], the dorsal determinant Bozozok to restrict axis formation in zebrafish [#6], the kinases PBK and BCR to control proliferation and apoptosis [#10], and p53 in an MDM2-dependent manner to limit p53 stability and tumor suppression [#19]. LNX1 also performs non-degradative ubiquitination of RhoC (but not RhoA), activating RhoC by acting on the RhoGDI-RhoC interaction under negative control by LIS1 [#22]. In neurons LNX1 is concentrated postsynaptically where it stabilizes EphB1/EphB2 receptors at the membrane by preventing their internalization, a function required for mossy fiber targeting, dendritic spine and NMDAR-dependent synaptic maturation, and social memory [#15, #18, #23]; it additionally ubiquitinates the glycine transporter GlyT2 at a C-terminal lysine cluster to regulate transport activity [#16]. A RING-deficient neuronal isoform, LNX1p70, retains scaffolding activity and can promote ubiquitination of shared substrates by recruiting other E3 ligases [#12].\",\n  \"teleology\": [\n    {\n      \"year\": 1998,\n      \"claim\": \"Established LNX1 as a Numb-interacting protein, defining the molecular handle (the Numb PTB domain binding the LDNPAY motif) that would later connect LNX1 to Notch regulation.\",\n      \"evidence\": \"Yeast two-hybrid with mutational and peptide-competition validation\",\n      \"pmids\": [\"9535908\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No enzymatic activity yet attributed to LNX1\", \"Functional consequence of the interaction unknown at this stage\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Defined LNX1 as a functional RING E3 ligase that ubiquitinates and degrades Numb, mechanistically linking LNX1 to enhanced Notch signalling.\",\n      \"evidence\": \"In vitro ligase assay, RING cysteine active-site mutagenesis, in vivo ubiquitination and proteasome-inhibitor experiments\",\n      \"pmids\": [\"11782429\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"E2 partner not identified\", \"Structural basis of catalysis unknown\", \"Which PDZ domains recognize which substrates not yet mapped\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Showed LNX1 can oligomerize and bind Numb simultaneously, framing LNX1 as a molecular scaffold in addition to a ligase.\",\n      \"evidence\": \"Protein interaction and yeast two-hybrid assays of PDZ- and RING-mediated oligomerization\",\n      \"pmids\": [\"11922143\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional importance of oligomerization for catalysis untested\", \"No in vitro reconstitution\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Identified PDZ-domain-based substrate/partner recognition (CAR via PDZ2), beginning the mapping of how individual PDZ domains select targets.\",\n      \"evidence\": \"Yeast two-hybrid, reciprocal in vivo/in vitro binding with domain mapping, colocalization\",\n      \"pmids\": [\"12468544\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether CAR is a ubiquitination substrate not shown\", \"Physiological role of LNX1-CAR interaction unknown\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Demonstrated an in vivo developmental role: LNX1 K48-polyubiquitinates Bozozok to restrict dorso-ventral axis formation, validating substrate-binding-motif-dependent degradation in a whole animal.\",\n      \"evidence\": \"Zebrafish morpholino knockdown, K48 ubiquitination assays, genetic epistasis, substrate motif mutagenesis\",\n      \"pmids\": [\"19668196\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mammalian developmental relevance not addressed\", \"Which PDZ domain binds Boz not specified\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Extended the LNX1 interactome to the small GTPase RhoC via PDZ1, hinting at a non-canonical signalling output.\",\n      \"evidence\": \"Yeast two-hybrid, co-IP, subcellular localization, AP-1 reporter assay\",\n      \"pmids\": [\"19701800\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Ubiquitination of RhoC not yet demonstrated\", \"Mechanism linking RhoC relocalization to AP-1 activity unclear\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Broadened the LNX1 PDZ-domain interactome through array and phylogenetic approaches, supporting a general scaffolding function shared with MUPP1.\",\n      \"evidence\": \"Human protein array with co-IP validation; yeast two-hybrid with phylogenetic analysis\",\n      \"pmids\": [\"22087225\", \"21827680\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Most identified partners not tested as ubiquitination substrates\", \"Physiological significance of individual interactions untested\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified PBK and BCR as endogenous substrates and connected LNX1-mediated degradation to control of proliferation and apoptotic sensitivity.\",\n      \"evidence\": \"Yeast two-hybrid peptide library, in vitro and in vivo ubiquitination, proliferation and apoptosis assays\",\n      \"pmids\": [\"22889411\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"In vivo tumor relevance not tested\", \"Specificity determinants among many PDZ ligands unresolved\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Revealed isoform-specific regulation, showing LNX1p70 expression is restrained translationally by 5'UTR uORFs while LNX1p80 is controlled by proteasomal turnover.\",\n      \"evidence\": \"Luciferase reporter assays and uORF mutational analysis\",\n      \"pmids\": [\"25200495\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological triggers that relieve translational repression unknown\", \"Tissue distribution of isoform regulation not defined\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Mapped PDZ2-dependent recognition of liprin-\\u03b11 and identified the RING-deficient LNX1p70 isoform as a scaffold able to promote substrate ubiquitination by recruiting other E3 ligases (TRIM family).\",\n      \"evidence\": \"AP-MS interactome, in vitro ubiquitination, co-IP, PDZ-binding-motif mutagenesis\",\n      \"pmids\": [\"29121065\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Which recruited E3 catalyzes p70-dependent ubiquitination not directly shown\", \"Cellular consequences for most substrates untested\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Provided the structural mechanism: a Zn-RING-Zn module forms a catalytic heterodimer recruiting Ubc13/Ube2V2, explaining how LNX1 transfers ubiquitin.\",\n      \"evidence\": \"Crystal structure of LNX1 ubiquitination domain with Ubc13~Ub, mutagenesis, in vitro ubiquitination\",\n      \"pmids\": [\"29496391\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Chain-type specificity in vivo not fully defined\", \"Structure of PDZ-substrate engagement not solved\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Defined LNX1 neuronal substrate connexin36 and a developmental role for postsynaptic LNX1 in stabilizing EphB receptors and shaping CA3 mossy fiber circuitry.\",\n      \"evidence\": \"Co-IP/pull-down with PDZ2, ligase-competent vs ligase-dead comparison; Lnx1 knockout mice with morphology, complex Co-IP, proteasome inhibition, EphB2 rescue\",\n      \"pmids\": [\"30295974\", \"30185604\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct ubiquitination of EphB receptors not biochemically demonstrated\", \"How ligase activity and stabilization (non-degradative) coexist unresolved\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Expanded LNX1 into transporter regulation, immune/oncogenic signalling, and tumor suppressor control: RING-dependent GlyT2 ubiquitination, LDOC1-dependent pJAK2 degradation, and MDM2-dependent p53 destabilization, plus an essential synaptic role in social memory via the Lnx1-NMDAR-EphB2 complex.\",\n      \"evidence\": \"In vitro ubiquitination with lysine mutagenesis and LNX2 KO; co-IP and ubiquitination assays; CRISPR KO with p53 half-life and xenograft readouts; KO mice with electrophysiology, PSD fractionation, and viral rescue\",\n      \"pmids\": [\"31628376\", \"30634502\", \"31533005\", \"31772302\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Degree of functional overlap with LNX2 across substrates not delineated\", \"How LNX1 partitions between degradative and stabilizing roles in neurons unclear\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Connected LNX1 to disease contexts—NEK6 degradation controlled by miR-325-3p during M. tuberculosis infection, and post-temozolomide Numb degradation driving Notch1 activation and glioma stem cell expansion.\",\n      \"evidence\": \"miRNA targeting, Mir325 KO mice, NEK6 ubiquitination/STAT3 readouts; patient-derived xenograft gain/loss-of-function with Numb/NICD readouts and survival model\",\n      \"pmids\": [\"32487755\", \"33255632\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Therapeutic targetability not established\", \"Generality across tumor types untested\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Resolved a non-degradative output: LNX1 activates RhoC (not RhoA) via non-degrading ubiquitination acting on the RhoGDI-RhoC interaction, under LIS1 negative regulation, and reaffirmed EphB stabilization driving synaptogenesis.\",\n      \"evidence\": \"Isoform-specific in vitro ubiquitination, RhoGDI-RhoC interaction and LIS1 inhibition assays; KO mice with EphB internalization, spine morphology, and EphB2 rescue\",\n      \"pmids\": [\"36192543\", \"35531068\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Ubiquitin chain type/site on RhoC not fully defined\", \"How LIS1 mechanistically blocks LNX1 unresolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved how LNX1 selects between degradative and non-degradative/stabilizing fates for its many PDZ-bound substrates, and how isoform identity, E2 choice, and partner ligases dictate outcome in a given cellular context.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unifying model for substrate fate determination\", \"Structure of PDZ-substrate complexes lacking\", \"In vivo chain-type specificity per substrate undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [1, 6, 10, 13, 16]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [1, 6, 10, 16, 19, 22]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [2, 9, 12]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [22, 23]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [15, 23]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [1, 6, 10, 13]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [1, 21, 22, 19]},\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [15, 16, 18, 23]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [6, 15, 23]}\n    ],\n    \"complexes\": [\n      \"LNX1-NMDAR-EphB2 postsynaptic complex\",\n      \"LDOC1-pJAK2-LNX1 complex\",\n      \"LNX1-MDM2-p53 complex\"\n    ],\n    \"partners\": [\n      \"NUMB\",\n      \"EphB2\",\n      \"RhoC\",\n      \"PPFIA1\",\n      \"CXadr\",\n      \"MDM2\",\n      \"LDOC1\",\n      \"GlyT2\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}