RNF11

RNF11 is a small RING-H2 protein that functions principally as a membrane-targeted scaffold and modulator of ubiquitin-ligase activity, coordinating inflammatory signaling, receptor trafficking, and TGFβ responses (PMID:19131965, PMID:20676133, PMID:28292929). Endosomal targeting to early and recycling compartments requires N-terminal myristoylation of Gly2 and S-palmitoylation of Cys4, and this acylation-dependent membrane anchoring is itself a prerequisite for RNF11 to be polyubiquitinated by the HECT ligases Itch and Nedd4 (PMID:20676133). As an essential component of the A20 ubiquitin-editing complex together with TAX1BP1 and Itch, RNF11 negatively regulates NF-κB and JNK signaling by limiting RIP1 and TRAF6 ubiquitination following TNF and LPS stimulation, an activity that depends on its myristoylation-driven endosomal localization (PMID:19131965, PMID:22507528). A biochemical basis for this restraint is that the RNF11 RING domain binds the E2 enzyme Ubc13 (UBE2N) and the Ubc13~ubiquitin conjugate with high affinity yet has minimal intrinsic ligase activity, allowing it to sequester Ubc13 away from E1 and active E3 ligases and thereby curtail Lys63-linked chain assembly (PMID:29537486). Through a PY/proline-rich motif RNF11 engages the HECT ligases SMURF2 and Itch (AIP4): it competes directly with SMAD7 for SMURF2, sequestering and activating SMURF2 on membranes to drive TGFβ-responsive gene expression, proliferation, and migration (PMID:14562029, PMID:28292929), and it recruits substrates including AMSH, GGA3, and KU80 to these ligases for ubiquitination (PMID:14755250, PMID:25195858, PMID:40876697). In the EGFR axis RNF11 acts as a functional ESCRT-0-associated factor binding STAM2, Eps15b, and Hrs to promote lysosomal degradation of activated EGFR, and upon sustained EGF stimulation translocates to the nucleus to transcriptionally upregulate COPII components (SEC23B, SEC24B, SEC24D) governing biosynthetic EGFR transport (PMID:23222715, PMID:27872256). RNF11 protein is sequestered into Lewy bodies in idiopathic Parkinson's disease brains (PMID:17917589).

1. 2003 Medium

   Established RNF11 as a PY-motif partner of HECT-type E3 ligases, defining the binding module through which it would later be shown to recruit substrates and modulate ligase activity.

   Evidence GST pulldown, co-IP, and reporter assays mapping PY-motif interactions with Smurf2 and AIP4/Itch in mammalian cells

   PMID:14559117 PMID:14562029

   Open questions at the time

   • Did not establish whether RNF11 is itself catalytically active or purely a scaffold
   • Functional consequence beyond reporter-level TGFβ readout not defined
2. 2004 Medium

   Showed RNF11 acts as a substrate adaptor by recruiting AMSH to Smurf2 for proteasomal degradation, providing the first concrete example of RNF11-directed ubiquitination of a defined target.

   Evidence Yeast two-hybrid, co-IP, ubiquitination and proteasome-inhibitor experiments in mammalian cells

   PMID:14755250

   Open questions at the time

   • AMSH binding is RING- and PY-motif-independent; the binding determinant remains undefined
   • Physiological context of AMSH turnover not established
3. 2009 High

   Defined RNF11 as an essential subunit of the A20 ubiquitin-editing complex, placing it at the center of negative regulation of NF-κB and JNK inflammatory signaling.

   Evidence siRNA knockdown, stimulus-dependent co-IP, and RIP1/TRAF6 ubiquitination assays in mammalian cells

   PMID:19131965

   Open questions at the time

   • Molecular mechanism by which RNF11 limits RIP1/TRAF6 ubiquitination not resolved at this stage
   • Whether RNF11 contributes catalytic or adaptor function within the complex unclear
4. 2010 High

   Identified the acylation code (Gly2 myristoylation, Cys4 palmitoylation) that targets RNF11 to early and recycling endosomes, and showed membrane anchoring is required for RNF11 to be ubiquitinated by Itch and Nedd4.

   Evidence Confocal microscopy with endosomal markers, site-directed mutagenesis of acylation sites, in vivo ubiquitination assays

   PMID:20676133

   Open questions at the time

   • How endosomal localization is mechanistically coupled to signaling outputs not defined here
   • Regulation of palmitoylation dynamics unknown
5. 2012 High

   Connected RNF11 endosomal localization to its signaling function, demonstrating the myristoylation domain is required for full NF-κB suppression and A20-complex association in neural cells, and that RNF11 confers cytoprotection.

   Evidence shRNA knockdown, luciferase reporters, p65 translocation, mutagenesis, and cytokine measurements in primary neurons and microglia

   PMID:22507528 PMID:22975135

   Open questions at the time

   • Microglial A20 interaction shown by single co-IP without reciprocal validation
   • Direct biochemical link between endosomal residence and RIP1/TRAF6 editing not established
6. 2012 High

   Placed RNF11 within ESCRT-0-dependent receptor trafficking, showing it controls the rate of activated EGFR lysosomal degradation and downstream ERK signaling.

   Evidence Co-IP with STAM2/Eps15b/Hrs, gain- and loss-of-function EGFR degradation and ERK1/2 phosphorylation assays, confocal microscopy

   PMID:23222715

   Open questions at the time

   • Whether RNF11 catalytic activity or adaptor role drives EGFR sorting not separated
   • Relationship between ESCRT-0 role and A20-complex role unaddressed
7. 2014 High

   Defined RNF11 sorting determinants (Ac-LL motifs recognized by GGA VHS domains) and showed RNF11 reciprocally controls GGA3 stability by recruiting Itch, establishing a feedback between cargo sorting and ubiquitination.

   Evidence Mutagenesis of Ac-LL motifs, co-IP, ubiquitination assays, siRNA, confocal microscopy

   PMID:25195858

   Open questions at the time

   • Physiological cargo whose sorting depends on the RNF11-GGA3-Itch axis not identified
   • Interplay with acylation-based endosomal targeting not resolved
8. 2016 High

   Revealed an unexpected nuclear/transcriptional arm of RNF11 function, integrating EGFR degradation with biosynthetic transport via transcriptional upregulation of COPII components.

   Evidence Live imaging, subcellular fractionation, RNAi, flow cytometry, RUSH transport assays

   PMID:27872256

   Open questions at the time

   • Mechanism of RNF11 nuclear translocation and DNA/transcription-machinery engagement undefined
   • Whether transcriptional role requires RING or ubiquitin activity unknown
9. 2017 High

   Provided the mechanistic basis for RNF11's TGFβ role: it competes with SMAD7 for SMURF2 and activates SMURF2 on membranes while suppressing its auto-ubiquitylation, driving migration.

   Evidence Proteomic screen, in vitro reconstitution of the SMURF2·RNF11 complex, competition binding and ubiquitylation assays, siRNA with migration readouts

   PMID:28292929

   Open questions at the time

   • Physiological substrates of membrane-activated SMURF2 not enumerated
   • How this axis is balanced against RNF11's negative regulatory roles unclear
10. 2018 High

    Explained how a catalytically weak RING ligase exerts negative regulation: RNF11 binds Ubc13 and the Ubc13~Ub conjugate with high affinity and outcompetes E1 and active E3s, sequestering the E2 to limit K63 chain assembly.

    Evidence In vitro binding, competition assays against E1 and active E3, ubiquitin chain assembly assays

    PMID:29537486

    Open questions at the time

    • Cellular demonstration of Ubc13 sequestration as the operative mechanism for NF-κB control not provided
    • Stoichiometry relative to physiological Ubc13 pools unknown
11. 2023 Medium

    Showed the RNF11 RING zinc sites are a chemical target of cisplatin, which ejects zinc, unfolds and oligomerizes RNF11, and disrupts the UBE2N interaction, suggesting a drug-modulated mechanism.

    Evidence UV-vis, ESI-MS, CD, NMR, gel electrophoresis, and pull-down on purified RNF11

    PMID:36906278

    Open questions at the time

    • Cellular relevance of RNF11 platination to cisplatin response not demonstrated
    • In vitro only; functional downstream consequences in cells untested
12. 2025 Medium

    Extended RNF11 substrate adaptor function to DNA repair, showing it ubiquitinates KU80 and that its loss arrests cells and sensitizes tumors to chemotherapy.

    Evidence CRISPR knockout, co-IP, ubiquitination assays, cell cycle analysis, and 5-FU xenograft models

    PMID:40876697

    Open questions at the time

    • Which HECT ligase partner (if any) executes KU80 ubiquitination not defined
    • Mechanistic link between KU80 turnover and G1 arrest single-lab only
13. 2025 Low

    Reported a candidate role for RNF11 in GPCR heterodimer function by enhancing MC3R/GHSR-1A heterodimerization and cAMP output.

    Evidence FRET heterodimerization and EPAC cAMP biosensor assays in overexpression systems

    PMID:41410731

    Open questions at the time

    • Overexpression only with no endogenous validation
    • No mechanism connecting RNF11 ubiquitin/scaffold activity to receptor dimerization
14. 2020 Medium

    Implicated RNF11 in neuronal dopamine homeostasis, where it negatively regulates stimulated dopamine release and dopamine transporter activity/expression.

    Evidence RNAi and overexpression in Drosophila dopaminergic neurons, optogenetic stimulation, fast-scan cyclic voltammetry, qRT-PCR

    PMID:33176188

    Open questions at the time

    • Molecular target through which RNF11 controls DAT not identified
    • Mammalian conservation of the dopamine phenotype untested

• How RNF11's distinct activities — Ubc13 sequestration, HECT-ligase substrate recruitment, ESCRT-0 trafficking, and nuclear transcriptional control — are coordinated within a single small protein, and how this relates to its sequestration in Parkinson's disease Lewy bodies, remains unresolved.
• No unified model integrating cytoplasmic, endosomal, and nuclear pools
• Disease relevance of Lewy-body sequestration functionally uncharacterized
• Endogenous in vivo demonstration of substrate ubiquitination across most reported targets lacking