Affinage

NUDT16L1

Tudor-interacting repair regulator protein · UniProt Q9BRJ7

Length
211 aa
Mass
23.3 kDa
Annotated
2026-06-10
18 papers in source corpus 12 papers cited in narrative 12 extracted findings
Cross-family judge vs UniProt: Affinage preferred faithfulness: 7/7 claims corpus-supported (100%)

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

NUDT16L1 (TIRR) is an RNA-binding regulator of the DNA damage response that controls 53BP1 activity by directly binding its tandem Tudor domain (PMID:28241136). High-resolution crystal structures show that the TIRR N-terminal region and L8-loop engage 53BP1 Tudor through three loops, masking the methyl-lysine binding surface that 53BP1 otherwise uses to read H4K20me2 chromatin marks; a TIRR-specific histidine (H106) and an essential arginine are central to this interface, and these residues distinguish TIRR from its homolog NUDT16, which does not bind 53BP1 (PMID:29844495, PMID:29967538, PMID:30002377). By occluding this surface, TIRR prevents 53BP1 recruitment to double-strand breaks and dampens DNA repair, while a parallel interaction blocks 53BP1 binding to dimethylated p53 (K382me2), suppressing p53-dependent transcription; loss of TIRR hyperactivates p53 and is selectively lethal in p53-proficient tumors (PMID:28241136, PMID:33961797). TIRR inhibition is relieved upon DNA damage through competing RNAs that bind the same TIRR surface as 53BP1—DSB-derived hairpin RNAs and the NEAT1_1 lncRNA isoform dissociate the TIRR/53BP1 complex in a cell-cycle-dependent manner (PMID:29967538, PMID:36288694, PMID:39349456)—and through DTX3L-mediated ubiquitination of TIRR at K187, which drives XPO1-dependent nuclear export and degradation (PMID:39632881). Beyond 53BP1 regulation, TIRR couples to mRNA metabolism, binding selected mRNAs and the export factor XPO1 to direct nuclear RNA export and P-body formation during the DDR (PMID:39119906). In mice, TIRR loss activates p53 to confer cancer protection at the cost of systemic metabolic imbalance (PMID:38861384). In specific cancer contexts NUDT16L1 localizes to mitochondria, binds NAD-capped RNAs, and suppresses ferroptosis (PMID:39317106), and its transcription is directly activated by EGR1 to protect spermatogonial stem cells from oxidative stress (PMID:41521514).

Mechanistic history

Synthesis pass · year-by-year structured walk · 10 steps
  1. 2017 High

    Established that TIRR is a direct negative regulator of 53BP1, answering how 53BP1 recruitment to breaks is held in check before damage.

    Evidence Co-IP, overexpression/depletion functional assays, and live-cell DSB foci imaging in human cells

    PMID:28241136

    Open questions at the time
    • Did not define the atomic basis of the TIRR/53BP1 interface
    • Mechanism of RNA-driven dissociation not yet established
  2. 2018 High

    Crystal structures resolved how TIRR masks the 53BP1 Tudor methyl-lysine pocket and identified the specific residues (H106, an essential arginine) that confer specificity, explaining why the homolog NUDT16 cannot bind.

    Evidence X-ray crystallography of TIRR-53BP1 Tudor complexes with site-directed mutagenesis, DSB foci and repair assays, and RNA binding assays across three independent studies

    PMID:29844495 PMID:29967538 PMID:30002377

    Open questions at the time
    • Identity of the physiological dissociating RNA species in cells not yet defined
    • How damage signaling triggers dissociation in vivo not fully resolved
  3. 2021 High

    Extended TIRR's regulatory reach beyond chromatin to p53, showing it blocks the 53BP1 Tudor-K382me2-p53 interaction and thereby restrains p53 transactivation, defining a synthetic vulnerability in p53-proficient tumors.

    Evidence Biochemical Tudor-K382me2 binding assays, gene expression analysis on TIRR loss, and cell viability assays

    PMID:33961797

    Open questions at the time
    • Cell-type specificity of the p53 axis not fully mapped
    • Did not address how this is coordinated with the DSB-recruitment function
  4. 2022 Medium

    Identified the molecular trigger for relieving TIRR inhibition after damage: DSB-transcribed hairpin RNAs bind the same TIRR residues as 53BP1 and competitively dissociate the complex.

    Evidence RNA binding assays, mutagenesis mapping of the RNA-TIRR surface, RNA Pol II inhibition, and cell-based dissociation assays

    PMID:36288694

    Open questions at the time
    • Single lab; reciprocal validation of the in-cell hairpin species limited
    • Kinetics relative to RIF1/ATM-driven dissociation not resolved
  5. 2024 Medium

    Defined NEAT1_1 lncRNA as the primary cellular RNA partner of TIRR and linked its TDP-43-dependent production to cell-cycle-dependent control of 53BP1.

    Evidence iCLIP, Co-IP, cell-cycle synchronization, and TDP-43 functional assays

    PMID:39349456

    Open questions at the time
    • Single lab; relationship between NEAT1_1 and DSB hairpin RNA competition not reconciled
    • Quantitative contribution of TDP-43 in vivo not established
  6. 2024 High

    Revealed a degradative arm of TIRR regulation, showing DTX3L ubiquitinates TIRR at K187 to drive XPO1-dependent nuclear export and degradation, coupling TIRR turnover to repair-pathway choice and PARP inhibitor sensitivity.

    Evidence Ubiquitination assays, K187 mutagenesis, XPO1 inhibition, fractionation, and PARP inhibitor sensitivity assays

    PMID:39632881

    Open questions at the time
    • How RNA-driven and ubiquitination-driven dissociation are temporally coordinated unclear
    • Generality of DTX3L overexpression effect across cancer types not fully tested
  7. 2024 Medium

    Expanded TIRR function to mRNA metabolism, demonstrating XPO1-coupled mRNA export and P-body involvement during the DDR.

    Evidence RNA-IP, Co-IP with XPO1, fluorescence microscopy of P-body co-localization, and depletion readouts of RNA export

    PMID:39119906

    Open questions at the time
    • Single lab single study
    • Identity and fate of the exported mRNA cargo not defined
  8. 2024 Medium

    Identified a context-specific mitochondrial role for NUDT16L1 in binding NAD-capped RNAs and suppressing ferroptosis in colon cancer.

    Evidence Subcellular fractionation, NAD-capped RNA binding assays, ferroptosis assays, and a transgenic mouse model

    PMID:39317106

    Open questions at the time
    • Mechanistic link to the nuclear 53BP1/RNA functions unclear
    • Generality beyond colon cancer not established
  9. 2024 Medium

    Placed TIRR upstream of organismal phenotypes via p53, showing tissue-specific knockouts produce cancer protection alongside metabolic imbalance in a p53-dependent manner.

    Evidence Conditional/tissue-specific mouse knockouts, metabolic phenotyping, and p53 deletion epistasis

    PMID:38861384

    Open questions at the time
    • Molecular link between TIRR and tissue metabolism beyond p53 not detailed
    • Human relevance of metabolic phenotype not addressed
  10. 2026 Medium

    Established a transcriptional input to NUDT16L1, with EGR1 directly activating its promoter to confer oxidative-stress protection in spermatogonial stem cells.

    Evidence ChIP, luciferase reporter assays, overexpression/knockdown with ROS/apoptosis readouts, and a mouse testicular ischemia-reperfusion model

    PMID:41521514

    Open questions at the time
    • Single lab
    • Downstream effectors connecting NUDT16L1 to ROS reduction not defined

Open questions

Synthesis pass · forward-looking unresolved questions
  • How TIRR's distinct activities—53BP1/p53 inhibition, mRNA export, and mitochondrial NAD-RNA binding—are integrated and switched between under different cellular states remains unresolved.
  • No unifying model linking nuclear and mitochondrial functions
  • Hierarchy among competing dissociation mechanisms (hairpin RNA, NEAT1_1, ubiquitination) unestablished

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0003723 RNA binding 5 GO:0098772 molecular function regulator activity 4
Localization
GO:0005634 nucleus 2 GO:0005739 mitochondrion 1
Pathway
R-HSA-73894 DNA Repair 3 R-HSA-8953854 Metabolism of RNA 2

Evidence

Reading pass · 12 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2017 TIRR (NUDT16L1) directly binds the tandem Tudor domain of 53BP1 and masks its H4K20me2 histone methyl-lysine binding motif, preventing 53BP1 recruitment to DNA double-strand breaks. Upon DNA damage, ATM phosphorylates 53BP1 and recruits RIF1 to dissociate the 53BP1-TIRR complex. Overexpression of TIRR impedes 53BP1 localization to DSBs, while depletion of TIRR destabilizes 53BP1 in the nuclear-soluble fraction. Co-immunoprecipitation, overexpression/depletion functional assays, live-cell imaging of DSB foci Nature High 28241136
2018 Crystal structure (1.76 Å) of TIRR in complex with the 53BP1 tandem Tudor domain reveals that the N-terminal region (residues 10–24) and the L8-loop of TIRR interact with 53BP1 Tudor through three loops (L1, L3, L1'), blocking the H4K20me2-binding surface. A TIRR-specific histidine (H106), absent from the homolog NUDT16, is essential for 53BP1 Tudor binding; mutations mimicking TIRR binding modules restore disrupted NUDT16-53BP1 Tudor interaction. X-ray crystallography, site-directed mutagenesis, binding assays Nature communications High 29844495
2018 X-ray crystal structure of TIRR bound to 53BP1 tandem Tudor domain reveals that an essential TIRR arginine residue is central to an intricate binding area that blocks the methylated-chromatin-binding surface of 53BP1. A 53BP1 separation-of-function mutation abolishing TIRR-mediated regulation renders 53BP1 hyperactive at DSBs. TIRR-interacting RNA molecules relieve this inhibition, providing proof-of-principle of RNA-triggered 53BP1 recruitment to DSBs. X-ray crystallography, site-directed mutagenesis, cell-based DSB foci assays, RNA binding assays Nature structural & molecular biology High 29967538
2018 Crystal structure of TIRR–53BP1 tandem Tudor domain complex shows three TIRR loops masking the methylated lysine-binding pocket of 53BP1 TTD, competing with histone H4K20 methylation. Key interaction residues were mapped and their mutation abolishes complex formation. NUDT16 does not directly interact with 53BP1 due to absence of key binding residues. TIRR suppresses relocation of 53BP1 to DNA lesions and 53BP1-dependent DNA damage repair. X-ray crystallography, site-directed mutagenesis, Co-IP, DSB repair assays Nature communications High 30002377
2021 TIRR inhibits complex formation between the Tudor domain of 53BP1 and dimethylated p53 (K382me2), thereby suppressing p53 transcriptional activation of target genes. Loss of TIRR causes an aberrant increase in p53 gene transactivation, affecting p53-mediated cell-fate programs. TIRR depletion is selectively not tolerated in p53-proficient tumors. Biochemical binding assays (Tudor domain–K382me2 p53 interaction), gene expression analysis upon TIRR loss, cell viability assays Molecular cell High 33961797
2022 RNA with a hairpin secondary structure transcribed at DSBs by RNA polymerase II promotes TIRR/53BP1 complex dissociation. This hairpin RNA binds to the same residues on TIRR as 53BP1, providing the mechanistic basis for RNA-driven complex separation after DNA damage. RNA binding assays, mutagenesis mapping of RNA-TIRR interaction surface, cell-based TIRR/53BP1 dissociation assays, RNA polymerase II inhibition Cell reports Medium 36288694
2024 NEAT1 long non-coding RNA (specifically the short isoform NEAT1_1, enriched in G1 phase) is the primary RNA partner of TIRR within cells, identified by iCLIP. NEAT1_1 binding destabilizes the TIRR/53BP1 complex, promoting 53BP1 function in a cell-cycle-dependent manner. TDP-43 modulates the TIRR/53BP1 complex by promoting NEAT1_1 production. iCLIP (individual-nucleotide resolution UV crosslinking and immunoprecipitation), Co-IP, cell-cycle synchronization, TDP-43 functional assays Nature communications Medium 39349456
2024 DTX3L ubiquitinates TIRR at lysine 187, facilitating XPO1-mediated nuclear export and subsequent degradation of TIRR upon DNA damage. This relieves TIRR-mediated inhibition of 53BP1, regulating NHEJ pathway activity and PARP inhibitor sensitivity. DTX3L overexpression (as in prostate cancers) decreases TIRR levels, impairs HR, and induces chromosomal instability. Ubiquitination assays, nuclear export inhibition (XPO1 inhibitor), site-directed mutagenesis (K187), co-immunoprecipitation, cellular fractionation, PARP inhibitor sensitivity assays Nature communications High 39632881
2024 TIRR selectively binds a subset of mRNAs in response to DNA damage and interacts with the nuclear export protein Exportin-1 (XPO1/CRM1) through a nuclear export signal. TIRR and TIRR-bound RNA co-localize with processing bodies (P-bodies); TIRR depletion results in nuclear RNA retention and impaired P-body formation, linking TIRR's RNA-binding activity to mRNA nuclear export and storage during the DDR. RNA immunoprecipitation, co-immunoprecipitation with XPO1, fluorescence microscopy (P-body co-localization), TIRR depletion with mRNA export/P-body formation readouts Nucleic acids research Medium 39119906
2024 NUDT16L1 localizes to mitochondria in colon cancer cells, where it prevents mitochondrial DNA leakage upon ferroptosis induction. It promotes ferroptosis insensitivity by binding directly to NAD-capped RNAs and indirectly enhancing expression of ferroptosis repressor and mitochondrial genes through MALAT1. Subcellular fractionation/mitochondrial localization, NAD-capped RNA binding assays, NUDT16L1 overexpression/knockdown with ferroptosis assays, transgenic mouse model Redox biology Medium 39317106
2024 Deletion of TIRR in mice selectively activates p53, protecting against cancer but causing systemic metabolic imbalance (overweight, insulin resistance). These metabolic and oncoprotective effects are dependent on p53. Tissue-specific models indicate glucose homeostasis is regulated primarily by TIRR expression in adipose tissue, and orexigenesis by TIRR expression in the CNS. Conditional/tissue-specific mouse knockout models, metabolic phenotyping, p53 deletion epistasis Cell reports Medium 38861384
2026 EGR1 transcription factor directly binds the promoter of NUDT16L1 and activates its expression, establishing NUDT16L1 as a downstream effector of EGR1. Overexpression of NUDT16L1 alone reduces ROS and prevents cell death in spermatogonial stem cells under oxidative stress; silencing NUDT16L1 abolishes EGR1's protective effects against testicular ischemia-reperfusion injury in mice. Chromatin immunoprecipitation (ChIP), luciferase reporter assay, NUDT16L1 overexpression/knockdown with ROS/apoptosis readouts, mouse testicular IR injury model Cell biology international Medium 41521514

Source papers

Stage 0 corpus · 18 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2017 TIRR regulates 53BP1 by masking its histone methyl-lysine binding function. Nature 112 28241136
2018 Structural basis for recognition of 53BP1 tandem Tudor domain by TIRR. Nature communications 44 29844495
2018 Mechanism of 53BP1 activity regulation by RNA-binding TIRR and a designer protein. Nature structural & molecular biology 41 29967538
2021 TIRR inhibits the 53BP1-p53 complex to alter cell-fate programs. Molecular cell 28 33961797
2018 Molecular basis for the inhibition of the methyl-lysine binding function of 53BP1 by TIRR. Nature communications 23 30002377
2022 DNA double-strand break-derived RNA drives TIRR/53BP1 complex dissociation. Cell reports 14 36288694
2024 Overexpression of NUDT16L1 sustains proper function of mitochondria and leads to ferroptosis insensitivity in colorectal cancer. Redox biology 13 39317106
2024 NEAT1 modulates the TIRR/53BP1 complex to maintain genome integrity. Nature communications 10 39349456
2024 DTX3L-mediated TIRR nuclear export and degradation regulates DNA repair pathway choice and PARP inhibitor sensitivity. Nature communications 9 39632881
2024 Hypoglycemic Ability of Sericin-Derived Oligopeptides (SDOs) from Bombyx mori Yellow Silk Cocoons and Their Physiological Effects on Streptozotocin (STZ)-Induced Diabetic Rats. Foods (Basel, Switzerland) 6 39063270
2024 Oral Toxicity and Hypotensive Influence of Sericin-Derived Oligopeptides (SDOs) from Yellow Silk Cocoons of Bombyx mori in Rodent Studies. Foods (Basel, Switzerland) 5 39517289
2025 Pilot-Scale Production of Sericin-Derived Oligopeptides (SDOs) from Yellow Silk Cocoons: Peptide Characterization and Specifications. Foods (Basel, Switzerland) 4 39942094
2020 TIRR: a potential front runner in HDR race-hypotheses and perspectives. Molecular biology reports 4 32036573
2024 Endogenous p53 inhibitor TIRR dissociates systemic metabolic health from oncogenic activity. Cell reports 3 38861384
2013 Design and testing of a uniformly solar energy TIR-R concentration lenses for HCPV systems. Optics express 3 24514935
2025 Preventive and Therapeutic Effects of Sericin-Derived Oligopeptides (SDOs) from Yellow Silk Cocoons on Blood Pressure Lowering in L-NAME-Induced Hypertensive Rats. Foods (Basel, Switzerland) 2 40238512
2024 TIRR regulates mRNA export and association with P-bodies in response to DNA damage. Nucleic acids research 1 39119906
2026 Protective Role of the EGR1-Nudt16L1 Pathway in Spermatogonial Stem Cells Against Testicular Ischemia-Reperfusion Injury. Cell biology international 0 41521514

Missed literature

Know a paper Affinage missed for NUDT16L1? Flag it for the maintainers and the community.

No submissions yet.