RNF114

RNF114 is a RING-domain E3 ubiquitin ligase that functions as a versatile ubiquitin-chain writer at the intersection of DNA damage signaling, cell cycle control, innate immunity, and early embryonic development. Its tandem zinc-finger plus UIM module (ZnF2+ZnF3+UIM/Di19-UIM) acts as a reader of hybrid ADP-ribose–ubiquitin (MARUbe) marks, enabling selective recruitment to MARylated substrates such as PARP1, PARP7, and tankyrase, where it extends K11-linked polyubiquitin chains at DNA lesions and on ADP-ribosylated proteins (PMID:40634336, PMID:41039157, PMID:37878693). RNF114 ubiquitinates and destabilizes CIP/KIP CDK inhibitors (p21/p27/p57) to promote G1–S progression, degrades MAVS to negatively regulate type I interferon signaling, targets TRAF6 for K48-linked degradation to suppress osteoclastogenesis, and degrades TAB1 and CBX5 in oocytes to enable the maternal-to-zygotic transition (PMID:23645206, PMID:28625874, PMID:28708287, PMID:28073917, PMID:34104941). In T cells, RNF114 stabilizes A20 and IκBα to restrain NF-κB signaling, and the adaptor XAF1 recruits RNF114 to additional substrates including TRIM28 and junction plakoglobin (PMID:25165885, PMID:39532800, PMID:38095639).

1. 2008 Medium

   Establishing that RNF114 directly binds ubiquitin via a UIM domain resolved whether this RING-domain protein could serve as both a ubiquitin writer and reader.

   Evidence Cell-free ubiquitin-binding assay with purified RNF114

   PMID:18364390

   Open questions at the time

   • No E3 ligase activity demonstrated at this stage
   • Biological substrates unknown
   • Single binding assay without structural resolution
2. 2011 Medium

   Demonstrating that RNF114 is interferon-inducible and enhances NF-κB/IRF3 activation placed it within innate immune signaling, though the direct substrate remained unknown.

   Evidence Reporter assays, qRT-PCR, and subcellular fractionation in dsRNA-stimulated cells

   PMID:21571784

   Open questions at the time

   • No direct substrate identified
   • Overexpression-based system without loss-of-function validation
3. 2013 High

   Reconstitution of RNF114 E3 ligase activity toward p21/p27/p57 established it as a RING-dependent ubiquitin ligase governing G1–S cell cycle progression and senescence.

   Evidence In vitro ubiquitination assay, RING domain mutagenesis, flow cytometry, co-IP

   PMID:23645206

   Open questions at the time

   • Chain-linkage type on CIP/KIP substrates not specified
   • Physiological contexts beyond cell lines not tested
4. 2014 High

   Identification of RNF114 as a stabilizer of A20 and IκBα in T cells revealed a negative-regulatory arm of NF-κB signaling distinct from its substrate-degrading activities, while XAF1 was shown to function as an adaptor activating RNF114-mediated p21 degradation.

   Evidence Yeast two-hybrid, reciprocal co-IP, NF-κB reporter assay in T cells; XAF1 domain-deletion and ubiquitination assay

   PMID:24631332 PMID:25165885 PMID:25313037

   Open questions at the time

   • Mechanism by which RNF114 stabilizes A20 (non-degradative ubiquitin chain type?) unresolved
   • Structural basis of XAF1-RNF114 interaction not determined
5. 2017 High

   KO mouse studies established RNF114 as a physiological negative regulator of both MAVS-dependent innate immunity and RANKL-induced osteoclastogenesis through targeted degradation of MAVS and TRAF6, respectively, while in oocytes RNF114-mediated degradation of TAB1 was shown essential for the maternal-to-zygotic transition.

   Evidence RNF114 KO mice with IFN measurement, ubiquitination assays for MAVS; KO bone marrow macrophages with TRAF6 K48-ubiquitination assays; protein microarray substrate identification and embryo development rescue for TAB1

   PMID:28073917 PMID:28625874 PMID:28708287

   Open questions at the time

   • Relative contribution of MAVS degradation versus other substrates to antiviral phenotype unclear
   • Whether osteoclast phenotype is cell-autonomous not fully resolved
6. 2021 High

   Covalent engagement of RNF114 by nimbolide enabled its use as an E3 ligase in PROTAC-mediated targeted protein degradation, while identification of CBX5 as an oocyte substrate deepened the mechanistic understanding of RNF114 in zygotic genome activation.

   Evidence ABPP chemoproteomic profiling, PROTAC degradation of BRD4/BCR-ABL in cells; oocyte proteomics with genetic rescue of CBX5/TAB1 knockdown

   PMID:33513350 PMID:34104941

   Open questions at the time

   • Structural basis of nimbolide–RNF114 covalent interaction not fully resolved
   • Whether CBX5 is a direct or adaptor-mediated substrate unclear
7. 2022 Medium

   Validation of RNF114–MAVS interaction in human cells during VSV infection confirmed its role as a negative regulator of type I IFN, while K48-linked ubiquitination of EGR1 was proposed as a cancer-promoting mechanism.

   Evidence Co-IP, viral titer assays, in vivo lung infection model for MAVS; ubiquitination assay and siRNA knockdown for EGR1

   PMID:35069903 PMID:35545202

   Open questions at the time

   • EGR1 ubiquitination lacks in vitro reconstitution and independent replication
   • Mechanism of substrate selectivity between MAVS and other innate-immune targets unclear
8. 2023 High

   Discovery that RNF114 is recruited to DNA damage in a PAR-dependent manner to ubiquitinate PARP1 linked its E3 ligase function to the DNA damage response, and nimbolide-induced PARP trapping was shown to be synthetically lethal with BRCA mutations; separately, XAF1-VCP axis regulation of RNF114 stability was tied to JUP degradation and metastasis.

   Evidence In vitro ubiquitination of PARP1, laser-damage recruitment assay, BRCA synthetic lethality in vitro and in vivo; reciprocal co-IP, ubiquitination assay, and in vivo metastasis model for JUP/XAF1

   PMID:37878693 PMID:38095639

   Open questions at the time

   • PAR-binding domain versus MARUbe-reading domain contribution to recruitment not yet distinguished
   • In vivo therapeutic window of nimbolide-based PARP trapping undefined
9. 2024 High

   XAF1-dependent recruitment of RNF114 to TRIM28 for ubiquitination and degradation extended the adaptor model to oncogenic targets, with domain mutagenesis pinpointing XAF1 ZF7 as the RNF114-binding interface.

   Evidence Domain deletion mutagenesis, ubiquitination assay, xenograft tumor model

   PMID:39532800

   Open questions at the time

   • Direct structural data for XAF1 ZF7–RNF114 interface lacking
   • Substrate selectivity rules for XAF1-mediated targeting not defined
10. 2025 High

    Biochemical reconstitution and chemical probe studies resolved how RNF114 selectively reads hybrid MARUbe marks via its tandem ZnF+UIM module and extends K11-linked polyubiquitin chains, unifying its DNA-damage and ADP-ribosylation functions through a single substrate-recognition mechanism operating on PARP1, PARP7, and tankyrase.

    Evidence Non-hydrolysable ADPr-Ub probes, chemoenzymatic fluorescent Ub-ADPr probes, AlphaFold3 modeling, ITC/SPR binding assays, domain mutagenesis, laser-damage recruitment imaging, cell-based MARUbylation assays

    PMID:40634336 PMID:41039157

    Open questions at the time

    • No high-resolution experimental structure of the ZnF+UIM bound to MARUbe
    • Relative physiological contribution of K11 chains versus other linkages not resolved in vivo
    • Full scope of MARUbe substrates targeted by RNF114 undefined

• The structural basis of MARUbe recognition by RNF114's tandem ZnF+UIM, the rules governing XAF1-mediated substrate selection, and the physiological hierarchy among RNF114's many substrates across tissues remain unresolved.
• No experimental co-crystal or cryo-EM structure of RNF114 with MARUbe substrate
• No systematic comparison of substrate affinities in a single quantitative framework
• In vivo genetic dissection separating MARUbe-reading from general E3 functions not performed