{"gene":"RILPL2","run_date":"2026-06-10T06:43:36","timeline":{"discoveries":[{"year":2020,"finding":"Crystal structure of phospho-Rab8a (pT72) in complex with the RH2 domain of RILPL2 reveals a heterotetramer: RILPL2 forms a central α-helical dimer bridging two pRab8a molecules, with an X-shaped cap (X-cap) at the N termini that orients Arg residues toward pT72, establishing the structural basis for phospho-specific effector recognition of LRRK2-phosphorylated Rab GTPases.","method":"X-ray crystallography of pRab8a–RILPL2 RH2 domain complex; structural analysis of critical X-cap residues","journal":"Structure","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure with detailed mechanistic interpretation, multiple orthogonal structural analyses in a single rigorous study","pmids":["32017888"],"is_preprint":false},{"year":2021,"finding":"LRRK2-phosphorylated Rab10 recruits both RILPL2 and Myosin Va to the peri-centriolar region; the globular tail domain (GTD) of Myosin Va contains a high-affinity binding site for phospho-Rab10, and phosphoRab10 retains Myosin Va over pericentriolar membranes as shown by FLIP, thereby blocking ciliogenesis.","method":"Co-immunoprecipitation, fluorescence loss in photobleaching (FLIP) microscopy, phosphoRab10-dependent relocalization assay in RPE cells with pathogenic LRRK2","journal":"Life science alliance","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal binding assays, FLIP microscopy, and cell-based relocalization with multiple orthogonal methods in a single study","pmids":["33727250"],"is_preprint":false},{"year":2021,"finding":"RILPL2 over-expression blocks ciliogenesis in RPE cells independently of tau tubulin kinase recruitment to the mother centriole; without pathogenic LRRK2, RILPL2 is not essential for ciliogenesis.","method":"RILPL2 over-expression in RPE cells, ciliogenesis assay","journal":"Life science alliance","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — single lab, cell-based over-expression phenotype with mechanistic specificity noted","pmids":["33727250"],"is_preprint":false},{"year":2012,"finding":"RILPL2 localizes dynamically to the primary cilium and centrosome and is associated with tubulovesicular structures at the base of the cilium; depletion of RILPL2 (together with RILPL1) causes accumulation of signaling proteins in the ciliary membrane and prevents proper epithelial cell organization in 3D culture, indicating a role in regulating ciliary membrane protein concentration by promoting protein removal from the primary cilium.","method":"Live-cell microscopy, shRNA depletion, 3D culture epithelial organization assay","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — live imaging with functional depletion phenotype, though RILPL1 and RILPL2 were co-depleted limiting gene-specific resolution","pmids":["23264467"],"is_preprint":false},{"year":2009,"finding":"RILPL2 interacts with Myosin Va (MyoVa) and forms a complex with Rac1; overexpression of RILPL2 in hippocampal neurons increases spine-like protrusions, while shRNA knockdown reduces them (rescued by shRNA-insensitive RILPL2). RILPL2-induced Rac1 and PAK activation, as well as morphological changes, are blocked by a dominant-negative MyoVa tail or MyoVa shRNA, placing RILPL2 downstream of MyoVa in a Rac1-PAK signaling pathway controlling dendritic spine morphogenesis.","method":"Co-immunoprecipitation (RILPL2–MyoVa, RILPL2–Rac1), shRNA knockdown and rescue, overexpression in hippocampal neurons, Rac1/PAK activation assays","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, shRNA with rescue, epistasis via dominant-negative and shRNA, multiple orthogonal methods","pmids":["19812310"],"is_preprint":false},{"year":2019,"finding":"RILPL2 binds the globular tail domain (GTD) of myosin-5a and, together with melanophilin (Mlph), is required to activate myosin-5a motor function under physiological ionic conditions; Rab36 (a RILPL2 binding partner) further promotes this activation by stimulating RILPL2 interaction with the GTD, which then exposes the Mlph-binding site enabling full motor activation.","method":"ATPase assay, single-molecule motility assay, GST pulldown, analytical ultracentrifugation","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution with ATPase and single-molecule motility assays plus biochemical pulldowns, multiple orthogonal methods in one study","pmids":["31175157"],"is_preprint":false},{"year":2019,"finding":"RILPL2 interacts with TUBB3 and promotes its destabilization, leading to downregulation of breast cancer cell proliferation and migration and upregulation of PTEN expression; RILPL2 also reverses taxotere resistance by regulating the TUBB3/PTEN/AKT pathway.","method":"Co-immunoprecipitation (RILPL2–TUBB3), overexpression in vitro and in vivo tumor models, PTEN/AKT pathway analysis","journal":"American journal of cancer research","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, single Co-IP with limited mechanistic follow-up; no mutagenesis or reconstitution","pmids":["31497344"],"is_preprint":false},{"year":2026,"finding":"RILPL2 interacts with LDHA and reduces LDHA protein stability by recruiting the E3 ubiquitin ligase TRIM21 to promote K48-linked ubiquitination of LDHA, leading to proteasomal degradation of LDHA, thereby blocking glycolytic reprogramming and reducing lactate-dependent H3K18 lactylation in cervical cancer cells.","method":"Co-immunoprecipitation (RILPL2–LDHA, RILPL2–TRIM21), ubiquitination assay (K48-linkage), protein stability assay, H3K18 lactylation measurement","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — Co-IP with ubiquitination assay and downstream functional readout, but single lab with no mutagenesis or reconstitution","pmids":["42082464"],"is_preprint":false}],"current_model":"RILPL2 is a phospho-specific effector of LRRK2-phosphorylated Rab GTPases (particularly pRab8a and pRab10) whose RH2 domain forms an X-cap heterotetramer with phospho-Rabs to mediate downstream signaling; it regulates primary ciliogenesis and ciliary membrane composition, controls dendritic spine morphogenesis by linking Myosin Va to Rac1-PAK signaling, co-activates Myosin Va motor function together with melanophilin in a Rab36-dependent manner, and can promote LDHA ubiquitination/degradation via TRIM21 to suppress glycolytic reprogramming."},"narrative":{"mechanistic_narrative":"RILPL2 is a phospho-specific effector that couples LRRK2-phosphorylated Rab GTPases to cytoskeletal motors and ciliary regulation [PMID:32017888, PMID:33727250]. Its RH2 domain assembles a heterotetramer with phospho-Rab8a (pT72) in which a RILPL2 α-helical dimer bridges two phospho-Rab molecules and an N-terminal X-cap orients arginine residues toward the phosphorylated threonine, providing the structural basis for selective recognition of LRRK2-phosphorylated Rabs [PMID:32017888]. Through this axis, phospho-Rab10 co-recruits RILPL2 and Myosin Va to the peri-centriolar region and retains the motor over pericentriolar membranes, blocking ciliogenesis; RILPL2 overexpression suffices to suppress ciliogenesis in RPE cells [PMID:33727250]. RILPL2 localizes dynamically to the primary cilium and centrosome and promotes removal of signaling proteins from the ciliary membrane to control its composition [PMID:23264467]. Independently of the ciliary axis, RILPL2 binds the globular tail domain of Myosin Va and, together with melanophilin and the binding partner Rab36, activates Myosin Va motor function [PMID:31175157], and acts downstream of Myosin Va in a Rac1–PAK pathway driving dendritic spine morphogenesis [PMID:19812310]. A more recent activity links RILPL2 to metabolic control, where it recruits the E3 ligase TRIM21 to drive K48-linked ubiquitination and degradation of LDHA, suppressing glycolytic reprogramming [PMID:42082464].","teleology":[{"year":2009,"claim":"Established RILPL2 as a Myosin Va interactor that drives dendritic spine morphogenesis, defining its first functional role downstream of a motor protein in Rac1-PAK signaling.","evidence":"Reciprocal Co-IP, shRNA knockdown with rescue, and epistasis via dominant-negative MyoVa tail in hippocampal neurons","pmids":["19812310"],"confidence":"High","gaps":["Direct interaction interface on Myosin Va not mapped","How RILPL2 links MyoVa to Rac1/PAK activation mechanistically unresolved"]},{"year":2012,"claim":"Identified RILPL2 as a ciliary/centrosomal protein that limits ciliary membrane protein concentration, framing its role in cilium homeostasis.","evidence":"Live-cell microscopy, shRNA depletion (with RILPL1), and 3D epithelial organization assay","pmids":["23264467"],"confidence":"Medium","gaps":["RILPL1 and RILPL2 were co-depleted, limiting gene-specific attribution","Mechanism of ciliary protein removal not defined"]},{"year":2019,"claim":"Reconstituted RILPL2 as a co-activator of Myosin Va motor function with melanophilin, with Rab36 stimulating the RILPL2–GTD interaction to expose the Mlph-binding site.","evidence":"In vitro ATPase and single-molecule motility assays, GST pulldown, analytical ultracentrifugation","pmids":["31175157"],"confidence":"High","gaps":["Cellular context where Rab36-dependent activation operates not established","Relationship to the Rac1-PAK spine pathway unclear"]},{"year":2019,"claim":"Proposed a tumor-suppressive role via RILPL2–TUBB3 destabilization and PTEN/AKT regulation, extending RILPL2 function to cancer cell behavior.","evidence":"Co-IP, overexpression in breast cancer models, PTEN/AKT pathway analysis","pmids":["31497344"],"confidence":"Low","gaps":["Single Co-IP without mutagenesis or reconstitution","Direct versus indirect TUBB3 destabilization undefined","Not independently confirmed"]},{"year":2020,"claim":"Solved the structural basis for phospho-Rab recognition, showing the RH2 X-cap reads the LRRK2-phosphorylated threonine to define RILPL2 as a phospho-specific effector.","evidence":"X-ray crystallography of pRab8a–RILPL2 RH2 complex with X-cap residue analysis","pmids":["32017888"],"confidence":"High","gaps":["Downstream consequences of the heterotetramer in cells not addressed in this structural study","Selectivity across the full phospho-Rab repertoire not fully resolved"]},{"year":2021,"claim":"Connected phospho-Rab effector function to ciliogenesis, showing phospho-Rab10 co-recruits RILPL2 and Myosin Va to pericentriolar membranes to block cilium formation.","evidence":"Co-IP, FLIP microscopy, and phosphoRab10-dependent relocalization in RPE cells with pathogenic LRRK2","pmids":["33727250"],"confidence":"High","gaps":["Without pathogenic LRRK2, RILPL2 is not essential for ciliogenesis, leaving its baseline role open","How motor retention mechanistically prevents cilium assembly not detailed"]},{"year":2026,"claim":"Revealed a metabolic-regulatory function in which RILPL2 recruits TRIM21 to ubiquitinate and degrade LDHA, suppressing glycolytic reprogramming.","evidence":"Co-IP, K48-linkage ubiquitination assay, protein stability assay, and H3K18 lactylation measurement in cervical cancer cells","pmids":["42082464"],"confidence":"Medium","gaps":["No mutagenesis or reconstitution defining the RILPL2–TRIM21–LDHA interface","Whether this activity connects to the phospho-Rab or motor functions is unknown"]},{"year":null,"claim":"How RILPL2's distinct activities — phospho-Rab effector at the cilium, Myosin Va co-activator, and TRIM21 adaptor for LDHA degradation — are integrated or context-selected within a single cell remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unifying model linking the cytoskeletal, ciliary, and metabolic roles","Physiological versus pathogenic-LRRK2 contexts not disentangled"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[0,1,5]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[5]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[4,5]}],"localization":[{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[3]},{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[1,3]}],"pathway":[{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[4]}],"complexes":[],"partners":["RAB8A","RAB10","MYO5A","RAC1","MLPH","RAB36","TRIM21","LDHA"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q969X0","full_name":"RILP-like protein 2","aliases":["Rab-interacting lysosomal protein-like 2","p40phox-binding protein"],"length_aa":211,"mass_kda":24.0,"function":"Involved in cell shape and neuronal morphogenesis, positively regulating the establishment and maintenance of dendritic spines (By similarity). Plays a role in cellular protein transport, including protein transport away from primary cilia (By similarity). May function via activation of RAC1 and PAK1 (By similarity)","subcellular_location":"Cytoplasm, cytosol; Cytoplasm, cytoskeleton, microtubule organizing center, centrosome; Cell projection, cilium","url":"https://www.uniprot.org/uniprotkb/Q969X0/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/RILPL2","classification":"Not Classified","n_dependent_lines":22,"n_total_lines":1208,"dependency_fraction":0.018211920529801324},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/RILPL2","total_profiled":1310},"omim":[{"mim_id":"614093","title":"RAB-INTERACTING LYSOSOMAL PROTEIN-LIKE 2; RILPL2","url":"https://www.omim.org/entry/614093"},{"mim_id":"614092","title":"RAB-INTERACTING LYSOSOMAL PROTEIN-LIKE 1; RILPL1","url":"https://www.omim.org/entry/614092"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"},{"location":"Vesicles","reliability":"Additional"},{"location":"Primary cilium","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"bone marrow","ntpm":109.8}],"url":"https://www.proteinatlas.org/search/RILPL2"},"hgnc":{"alias_symbol":["MGC7036","FLJ30380","FLJ32372"],"prev_symbol":[]},"alphafold":{"accession":"Q969X0","domains":[{"cath_id":"1.20.58.1770","chopping":"28-107","consensus_level":"high","plddt":94.2188,"start":28,"end":107},{"cath_id":"1.20.5","chopping":"135-168","consensus_level":"medium","plddt":90.385,"start":135,"end":168}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q969X0","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q969X0-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q969X0-F1-predicted_aligned_error_v6.png","plddt_mean":77.19},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=RILPL2","jax_strain_url":"https://www.jax.org/strain/search?query=RILPL2"},"sequence":{"accession":"Q969X0","fasta_url":"https://rest.uniprot.org/uniprotkb/Q969X0.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q969X0/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q969X0"}},"corpus_meta":[{"pmid":"32017888","id":"PMC_32017888","title":"Structural Basis for Rab8a Recruitment of RILPL2 via LRRK2 Phosphorylation of Switch 2.","date":"2020","source":"Structure (London, England : 1993)","url":"https://pubmed.ncbi.nlm.nih.gov/32017888","citation_count":64,"is_preprint":false},{"pmid":"23264467","id":"PMC_23264467","title":"The Rilp-like proteins Rilpl1 and Rilpl2 regulate ciliary membrane content.","date":"2012","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/23264467","citation_count":52,"is_preprint":false},{"pmid":"33727250","id":"PMC_33727250","title":"LRRK2-phosphorylated Rab10 sequesters Myosin Va with RILPL2 during ciliogenesis blockade.","date":"2021","source":"Life science alliance","url":"https://pubmed.ncbi.nlm.nih.gov/33727250","citation_count":41,"is_preprint":false},{"pmid":"19812310","id":"PMC_19812310","title":"Myosin-Va-interacting protein, RILPL2, controls cell shape and neuronal morphogenesis via Rac signaling.","date":"2009","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/19812310","citation_count":31,"is_preprint":false},{"pmid":"31497344","id":"PMC_31497344","title":"RILPL2 regulates breast cancer proliferation, metastasis, and chemoresistance via the TUBB3/PTEN pathway.","date":"2019","source":"American journal of cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/31497344","citation_count":12,"is_preprint":false},{"pmid":"31175157","id":"PMC_31175157","title":"The cargo adaptor proteins RILPL2 and melanophilin co-regulate myosin-5a motor activity.","date":"2019","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/31175157","citation_count":10,"is_preprint":false},{"pmid":"39078518","id":"PMC_39078518","title":"RILPL2 as a potential biomarker for predicting enhanced T cell infiltration in non-small cell lung cancer.","date":"2024","source":"Immunologic research","url":"https://pubmed.ncbi.nlm.nih.gov/39078518","citation_count":0,"is_preprint":false},{"pmid":"42082464","id":"PMC_42082464","title":"RILPL2 suppresses metabolic reprogramming and progression of cervical cancer by attenuating LDHA protein stability and inhibiting H3K18 lactylation.","date":"2026","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/42082464","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.08.19.670962","title":"Structural basis for binding of RILPL1 to TMEM55B reveals a lysosomal platform for adaptor assembly through a conserved TBM motif","date":"2025-08-24","source":"bioRxiv","url":"https://doi.org/10.1101/2025.08.19.670962","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":6666,"output_tokens":2178,"usd":0.026334,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9177,"output_tokens":2779,"usd":0.05768,"stage2_stop_reason":"end_turn"},"total_usd":0.084014,"stage1_batch_id":"msgbatch_01CNoDbkChHEkgrJnL7BwtGJ","stage2_batch_id":"msgbatch_016Y4x9E9Wg5VQDANj9quSQD","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2020,\n      \"finding\": \"Crystal structure of phospho-Rab8a (pT72) in complex with the RH2 domain of RILPL2 reveals a heterotetramer: RILPL2 forms a central α-helical dimer bridging two pRab8a molecules, with an X-shaped cap (X-cap) at the N termini that orients Arg residues toward pT72, establishing the structural basis for phospho-specific effector recognition of LRRK2-phosphorylated Rab GTPases.\",\n      \"method\": \"X-ray crystallography of pRab8a–RILPL2 RH2 domain complex; structural analysis of critical X-cap residues\",\n      \"journal\": \"Structure\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure with detailed mechanistic interpretation, multiple orthogonal structural analyses in a single rigorous study\",\n      \"pmids\": [\"32017888\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"LRRK2-phosphorylated Rab10 recruits both RILPL2 and Myosin Va to the peri-centriolar region; the globular tail domain (GTD) of Myosin Va contains a high-affinity binding site for phospho-Rab10, and phosphoRab10 retains Myosin Va over pericentriolar membranes as shown by FLIP, thereby blocking ciliogenesis.\",\n      \"method\": \"Co-immunoprecipitation, fluorescence loss in photobleaching (FLIP) microscopy, phosphoRab10-dependent relocalization assay in RPE cells with pathogenic LRRK2\",\n      \"journal\": \"Life science alliance\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal binding assays, FLIP microscopy, and cell-based relocalization with multiple orthogonal methods in a single study\",\n      \"pmids\": [\"33727250\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"RILPL2 over-expression blocks ciliogenesis in RPE cells independently of tau tubulin kinase recruitment to the mother centriole; without pathogenic LRRK2, RILPL2 is not essential for ciliogenesis.\",\n      \"method\": \"RILPL2 over-expression in RPE cells, ciliogenesis assay\",\n      \"journal\": \"Life science alliance\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — single lab, cell-based over-expression phenotype with mechanistic specificity noted\",\n      \"pmids\": [\"33727250\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"RILPL2 localizes dynamically to the primary cilium and centrosome and is associated with tubulovesicular structures at the base of the cilium; depletion of RILPL2 (together with RILPL1) causes accumulation of signaling proteins in the ciliary membrane and prevents proper epithelial cell organization in 3D culture, indicating a role in regulating ciliary membrane protein concentration by promoting protein removal from the primary cilium.\",\n      \"method\": \"Live-cell microscopy, shRNA depletion, 3D culture epithelial organization assay\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — live imaging with functional depletion phenotype, though RILPL1 and RILPL2 were co-depleted limiting gene-specific resolution\",\n      \"pmids\": [\"23264467\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"RILPL2 interacts with Myosin Va (MyoVa) and forms a complex with Rac1; overexpression of RILPL2 in hippocampal neurons increases spine-like protrusions, while shRNA knockdown reduces them (rescued by shRNA-insensitive RILPL2). RILPL2-induced Rac1 and PAK activation, as well as morphological changes, are blocked by a dominant-negative MyoVa tail or MyoVa shRNA, placing RILPL2 downstream of MyoVa in a Rac1-PAK signaling pathway controlling dendritic spine morphogenesis.\",\n      \"method\": \"Co-immunoprecipitation (RILPL2–MyoVa, RILPL2–Rac1), shRNA knockdown and rescue, overexpression in hippocampal neurons, Rac1/PAK activation assays\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, shRNA with rescue, epistasis via dominant-negative and shRNA, multiple orthogonal methods\",\n      \"pmids\": [\"19812310\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"RILPL2 binds the globular tail domain (GTD) of myosin-5a and, together with melanophilin (Mlph), is required to activate myosin-5a motor function under physiological ionic conditions; Rab36 (a RILPL2 binding partner) further promotes this activation by stimulating RILPL2 interaction with the GTD, which then exposes the Mlph-binding site enabling full motor activation.\",\n      \"method\": \"ATPase assay, single-molecule motility assay, GST pulldown, analytical ultracentrifugation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution with ATPase and single-molecule motility assays plus biochemical pulldowns, multiple orthogonal methods in one study\",\n      \"pmids\": [\"31175157\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"RILPL2 interacts with TUBB3 and promotes its destabilization, leading to downregulation of breast cancer cell proliferation and migration and upregulation of PTEN expression; RILPL2 also reverses taxotere resistance by regulating the TUBB3/PTEN/AKT pathway.\",\n      \"method\": \"Co-immunoprecipitation (RILPL2–TUBB3), overexpression in vitro and in vivo tumor models, PTEN/AKT pathway analysis\",\n      \"journal\": \"American journal of cancer research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, single Co-IP with limited mechanistic follow-up; no mutagenesis or reconstitution\",\n      \"pmids\": [\"31497344\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"RILPL2 interacts with LDHA and reduces LDHA protein stability by recruiting the E3 ubiquitin ligase TRIM21 to promote K48-linked ubiquitination of LDHA, leading to proteasomal degradation of LDHA, thereby blocking glycolytic reprogramming and reducing lactate-dependent H3K18 lactylation in cervical cancer cells.\",\n      \"method\": \"Co-immunoprecipitation (RILPL2–LDHA, RILPL2–TRIM21), ubiquitination assay (K48-linkage), protein stability assay, H3K18 lactylation measurement\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — Co-IP with ubiquitination assay and downstream functional readout, but single lab with no mutagenesis or reconstitution\",\n      \"pmids\": [\"42082464\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"RILPL2 is a phospho-specific effector of LRRK2-phosphorylated Rab GTPases (particularly pRab8a and pRab10) whose RH2 domain forms an X-cap heterotetramer with phospho-Rabs to mediate downstream signaling; it regulates primary ciliogenesis and ciliary membrane composition, controls dendritic spine morphogenesis by linking Myosin Va to Rac1-PAK signaling, co-activates Myosin Va motor function together with melanophilin in a Rab36-dependent manner, and can promote LDHA ubiquitination/degradation via TRIM21 to suppress glycolytic reprogramming.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"RILPL2 is a phospho-specific effector that couples LRRK2-phosphorylated Rab GTPases to cytoskeletal motors and ciliary regulation [#0, #1]. Its RH2 domain assembles a heterotetramer with phospho-Rab8a (pT72) in which a RILPL2 α-helical dimer bridges two phospho-Rab molecules and an N-terminal X-cap orients arginine residues toward the phosphorylated threonine, providing the structural basis for selective recognition of LRRK2-phosphorylated Rabs [#0]. Through this axis, phospho-Rab10 co-recruits RILPL2 and Myosin Va to the peri-centriolar region and retains the motor over pericentriolar membranes, blocking ciliogenesis; RILPL2 overexpression suffices to suppress ciliogenesis in RPE cells [#1, #2]. RILPL2 localizes dynamically to the primary cilium and centrosome and promotes removal of signaling proteins from the ciliary membrane to control its composition [#3]. Independently of the ciliary axis, RILPL2 binds the globular tail domain of Myosin Va and, together with melanophilin and the binding partner Rab36, activates Myosin Va motor function [#5], and acts downstream of Myosin Va in a Rac1–PAK pathway driving dendritic spine morphogenesis [#4]. A more recent activity links RILPL2 to metabolic control, where it recruits the E3 ligase TRIM21 to drive K48-linked ubiquitination and degradation of LDHA, suppressing glycolytic reprogramming [#7].\",\n  \"teleology\": [\n    {\n      \"year\": 2009,\n      \"claim\": \"Established RILPL2 as a Myosin Va interactor that drives dendritic spine morphogenesis, defining its first functional role downstream of a motor protein in Rac1-PAK signaling.\",\n      \"evidence\": \"Reciprocal Co-IP, shRNA knockdown with rescue, and epistasis via dominant-negative MyoVa tail in hippocampal neurons\",\n      \"pmids\": [\"19812310\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Direct interaction interface on Myosin Va not mapped\",\n        \"How RILPL2 links MyoVa to Rac1/PAK activation mechanistically unresolved\"\n      ]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified RILPL2 as a ciliary/centrosomal protein that limits ciliary membrane protein concentration, framing its role in cilium homeostasis.\",\n      \"evidence\": \"Live-cell microscopy, shRNA depletion (with RILPL1), and 3D epithelial organization assay\",\n      \"pmids\": [\"23264467\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"RILPL1 and RILPL2 were co-depleted, limiting gene-specific attribution\",\n        \"Mechanism of ciliary protein removal not defined\"\n      ]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Reconstituted RILPL2 as a co-activator of Myosin Va motor function with melanophilin, with Rab36 stimulating the RILPL2–GTD interaction to expose the Mlph-binding site.\",\n      \"evidence\": \"In vitro ATPase and single-molecule motility assays, GST pulldown, analytical ultracentrifugation\",\n      \"pmids\": [\"31175157\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Cellular context where Rab36-dependent activation operates not established\",\n        \"Relationship to the Rac1-PAK spine pathway unclear\"\n      ]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Proposed a tumor-suppressive role via RILPL2–TUBB3 destabilization and PTEN/AKT regulation, extending RILPL2 function to cancer cell behavior.\",\n      \"evidence\": \"Co-IP, overexpression in breast cancer models, PTEN/AKT pathway analysis\",\n      \"pmids\": [\"31497344\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Single Co-IP without mutagenesis or reconstitution\",\n        \"Direct versus indirect TUBB3 destabilization undefined\",\n        \"Not independently confirmed\"\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Solved the structural basis for phospho-Rab recognition, showing the RH2 X-cap reads the LRRK2-phosphorylated threonine to define RILPL2 as a phospho-specific effector.\",\n      \"evidence\": \"X-ray crystallography of pRab8a–RILPL2 RH2 complex with X-cap residue analysis\",\n      \"pmids\": [\"32017888\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Downstream consequences of the heterotetramer in cells not addressed in this structural study\",\n        \"Selectivity across the full phospho-Rab repertoire not fully resolved\"\n      ]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Connected phospho-Rab effector function to ciliogenesis, showing phospho-Rab10 co-recruits RILPL2 and Myosin Va to pericentriolar membranes to block cilium formation.\",\n      \"evidence\": \"Co-IP, FLIP microscopy, and phosphoRab10-dependent relocalization in RPE cells with pathogenic LRRK2\",\n      \"pmids\": [\"33727250\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Without pathogenic LRRK2, RILPL2 is not essential for ciliogenesis, leaving its baseline role open\",\n        \"How motor retention mechanistically prevents cilium assembly not detailed\"\n      ]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Revealed a metabolic-regulatory function in which RILPL2 recruits TRIM21 to ubiquitinate and degrade LDHA, suppressing glycolytic reprogramming.\",\n      \"evidence\": \"Co-IP, K48-linkage ubiquitination assay, protein stability assay, and H3K18 lactylation measurement in cervical cancer cells\",\n      \"pmids\": [\"42082464\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No mutagenesis or reconstitution defining the RILPL2–TRIM21–LDHA interface\",\n        \"Whether this activity connects to the phospho-Rab or motor functions is unknown\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How RILPL2's distinct activities — phospho-Rab effector at the cilium, Myosin Va co-activator, and TRIM21 adaptor for LDHA degradation — are integrated or context-selected within a single cell remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No unifying model linking the cytoskeletal, ciliary, and metabolic roles\",\n        \"Physiological versus pathogenic-LRRK2 contexts not disentangled\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 1, 5]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [5]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [4, 5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [1, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [4]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"RAB8A\", \"RAB10\", \"MYO5A\", \"RAC1\", \"MLPH\", \"RAB36\", \"TRIM21\", \"LDHA\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}