Affinage

ANKZF1

tRNA endonuclease ANKZF1 · UniProt Q9H8Y5

Length
726 aa
Mass
80.9 kDa
Annotated
2026-04-28
16 papers in source corpus 12 papers cited in narrative 12 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

ANKZF1 is a peptidyl-tRNA hydrolase central to ribosome-associated quality control (RQC) that cleaves the tRNA acceptor arm of ubiquitinated nascent chain–tRNA complexes on stalled 60S ribosomal subunits, releasing proteasome-degradable nascent chains (PMID:30244831, PMID:29632312). Its catalytic mechanism depends on a conserved GSQ motif within the VLRF1 domain, which is positioned toward the CCA end of the P-site tRNA, with an ABCF-type ATPase (Arb1) stimulating cleavage in the pre-cleavage state (PMID:31189955). At mitochondria, ANKZF1 antagonizes CAT-tailing of stalled nascent chains to prevent toxic polypeptide aggregation and sequestration of mitochondrial chaperones and respiratory chain subunits; its mitochondrial targeting is autoinhibited by the N-terminal domain, which masks an internal matrix-targeting sequence relieved by stress signals such as oxidized sterols (PMID:29107329, PMID:29149595, PMID:38670305, PMID:41920018). ANKZF1 also functions as a mitophagy adaptor during PINK1-Parkin-mediated mitophagy, bridging polyubiquitinated outer mitochondrial membrane proteins (via its UBA domain) to LC3 on autophagosomes (via a LIR motif) (PMID:40730577).

Mechanistic history

Synthesis pass · year-by-year structured walk · 9 steps
  1. 2012 Medium

    Establishing that Vms1/ANKZF1 cooperates with Cdc48/p97 in protein degradation pathways revealed its initial functional link to ubiquitin-proteasome quality control beyond a generic stress factor.

    Evidence Genetic deletion of VMS1 in yeast with Cdc13 degradation assay and epistasis analysis with autophagy mutants

    PMID:22718752

    Open questions at the time
    • Substrate specificity beyond Cdc13 unknown
    • Direct enzymatic activity not yet identified
    • Mechanism of Vms1-Cdc48 cooperation unresolved
  2. 2013 Medium

    Demonstrating that the N-terminal domain autoinhibits mitochondrial targeting of Vms1, with oxidative stress relieving this block, established the regulated translocation mechanism that controls ANKZF1 function at mitochondria.

    Evidence Truncation mutants and live-cell imaging with laser-induced mitochondrial ROS in yeast

    PMID:23468520

    Open questions at the time
    • Identity of the stress-induced signal relieving autoinhibition not determined
    • Structural basis of intramolecular autoinhibition unknown
  3. 2014 Medium

    Showing that the Cdc48-Vms1 complex is required for 26S proteasome assembly revealed an unexpected role in maintaining the proteolytic machinery itself, beyond being a simple substrate adaptor.

    Evidence VMS1 deletion in yeast with native gel analysis of proteasome complexes and ubiquitin accumulation assays

    PMID:24351022

    Open questions at the time
    • Direct versus indirect role in proteasome biogenesis unclear
    • Not confirmed in mammalian cells
  4. 2017 High

    Two concurrent studies resolved the core mitochondrial function of Vms1/ANKZF1: it binds 60S ribosomes at the mitochondrial surface to antagonize Rqc2-mediated CAT-tailing, preventing toxic aggregation of stalled nascent chains inside mitochondria, and its mitochondrial translocation is controlled by an autoinhibitory N-terminal–MTD interaction relieved by the oxidized sterol ergosterol peroxide.

    Evidence Crystal structure of MTD–sterol complex, competitive binding assays, genetic deletion with mitochondrial import and aggregation assays, ribosome fractionation in yeast

    PMID:29107329 PMID:29149595

    Open questions at the time
    • Whether identical sterol-based activation applies to human ANKZF1 is unresolved
    • How Vms1 selects mitochondrial versus cytoplasmic stalled ribosomes unknown
  5. 2018 High

    Identification of ANKZF1/Vms1 as a peptidyl-tRNA hydrolase that specifically cleaves the tRNA acceptor arm on ubiquitinated 60S RNCs defined its catalytic activity, showing it depends on a conserved glutamine (analogous to eRF1) and requires upstream NEMF/Listerin-dependent ubiquitination to render the substrate susceptible.

    Evidence In vitro reconstitution with purified components, active-site mutagenesis, tRNA cleavage mapping in both yeast and human systems

    PMID:29632312 PMID:30244831

    Open questions at the time
    • Kinetic parameters of the hydrolase activity uncharacterized
    • Whether additional cofactors modulate activity in vivo unknown
  6. 2019 High

    Cryo-EM structures of Vms1 on the 60S subunit in pre- and post-cleavage states revealed how the VLRF1 domain positions its GSQ catalytic motif at the CCA end of P-site tRNA, how Y285 dislodges tRNA A73 to enable cleavage, and how the E-site ATPase Arb1 stimulates this reaction.

    Evidence Cryo-EM structure determination with functional mutagenesis and in vitro cleavage assays in yeast

    PMID:31189955

    Open questions at the time
    • No equivalent high-resolution structure of human ANKZF1 on 60S
    • Role of Arb1 ortholog in human RQC not tested
  7. 2024 Medium

    Loss-of-function studies in human glioblastoma cells demonstrated that ANKZF1 depletion causes CAT-tail accumulation in mitochondria, sequestering chaperones (HSP60, mtHSP70) and respiratory chain subunits, activating the UPRmt and triggering mitochondrial apoptosis—providing the first direct evidence of ANKZF1's anti-CAT-tail function in human cells.

    Evidence siRNA knockdown with mitochondrial fractionation, co-IP, membrane potential assay, and xenograft model in human glioblastoma cells

    PMID:38670305

    Open questions at the time
    • Findings from a single cancer cell type; generalizability to non-malignant cells untested
    • Whether ANKZF1 acts catalytically or structurally to suppress CAT-tailing in human cells not resolved
  8. 2025 Medium

    Discovery that ANKZF1 acts as a mitophagy adaptor during PINK1-Parkin-mediated mitophagy, bridging ubiquitinated outer mitochondrial membrane proteins to LC3 through its UBA domain and LIR motif (residues 333–336), expanded its function beyond RQC to organelle clearance.

    Evidence ANKZF1 knockout, co-IP of ANKZF1 with Parkin and LC3, LIR mutagenesis, and mitophagy flux assay in human cells

    PMID:40730577

    Open questions at the time
    • Single-lab finding; independent confirmation needed
    • Relative contribution of ANKZF1 versus other mitophagy receptors (OPTN, NDP52) not compared
    • Whether RQC and mitophagy adaptor functions are coordinated or independent is unclear
  9. 2026 Medium

    Mapping the human ANKZF1 N-terminal autoinhibition to residues 1–73 suppressing an internal matrix-targeting sequence at residues 231–240 provided the first structural rationale for regulated mitochondrial import of the human protein.

    Evidence Truncation mutants, GFP-fusion targeting assays, and molecular dynamics simulation in human cells

    PMID:41920018

    Open questions at the time
    • MD simulation-based structural model lacks experimental structural validation
    • Endogenous signal that relieves N-terminal autoinhibition in human cells not identified

Open questions

Synthesis pass · forward-looking unresolved questions
  • Key open questions remain: the identity of the physiological signal relieving ANKZF1 autoinhibition in human cells, a high-resolution structure of human ANKZF1 on the 60S subunit, whether the RQC peptidyl-tRNA hydrolase and mitophagy adaptor functions are coordinated, and the in vivo substrate spectrum of ANKZF1 beyond stalled nascent chains.
  • No high-resolution structure of human ANKZF1 on 60S ribosome
  • Physiological activating signal in human cells unidentified
  • Functional coordination between RQC and mitophagy roles untested

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0016787 hydrolase activity 3 GO:0140098 catalytic activity, acting on RNA 3 GO:0060090 molecular adaptor activity 1
Localization
GO:0005739 mitochondrion 5 GO:0005829 cytosol 2
Pathway
R-HSA-392499 Metabolism of proteins 5 GO:0005840 ribosome 4 R-HSA-9612973 Autophagy 1
Partners
LTN1MAP1LC3BNEMFPRKNVCPYWHAE
Complex memberships
60S RQC complex

Evidence

Reading pass · 12 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2018 ANKZF1 (human ortholog of yeast Vms1) is a peptidyl-tRNA hydrolase that induces specific cleavage in the tRNA acceptor arm of ubiquitinated nascent chain-tRNA/60S ribosomal complexes (60S RNCs), releasing proteasome-degradable ubiquitinated nascent chains linked to four 3'-terminal tRNA nucleotides. This activity requires NEMF- and Listerin-dependent ubiquitination of nascent chains, which accommodates the NC-tRNA in the P site and renders 60S RNCs resistant to Ptrh1 but susceptible to ANKZF1. In vitro reconstitution with purified components, peptidyl-tRNA hydrolase assay, tRNA cleavage mapping Molecular cell High 30244831
2018 Yeast Vms1 (founding member of the Vms1-like release factor 1 clade, of which ANKZF1 is the human ortholog) functions as a peptidyl-tRNA hydrolase on 60S ribosomal subunits carrying stalled nascent chains; its activity depends on a conserved catalytic glutamine residue analogous to eukaryotic release factor 1 (eRF1). Vms1 is a Cdc48 adaptor that cleaves the tRNA from ubiquitylated nascent chains prior to proteasomal degradation. In vitro peptidyl-tRNA hydrolase assay, active-site mutagenesis (catalytic Gln), evolutionary sequence analysis, Co-IP Nature High 29632312
2019 Cryo-EM structures of yeast Vms1 (ANKZF1 ortholog) bound to 60S ribosomal subunits in pre- and post-cleavage states reveal that Vms1 binds via its VLRF1, zinc finger, and ankyrin domains. The VLRF1 domain projects its catalytic GSQ motif toward the CCA end of the P-site tRNA, and residue Y285 dislodges tRNA A73 to enable nucleolytic cleavage. The ABCF-type ATPase Arb1 occupies the E-site in the pre-cleavage state, stabilizing the delocalized A73 and stimulating Vms1-dependent tRNA cleavage. Cryo-EM structure determination, functional mutagenesis, in vitro cleavage assay Nature High 31189955
2017 Yeast Vms1 (ANKZF1 ortholog) binds to 60S ribosomes at the mitochondrial surface and antagonizes Rqc2-mediated CAT-tailing of stalled nascent chains targeted to mitochondria, thereby facilitating mitochondrial import and directing aberrant polypeptides to intra-mitochondrial quality control. In the absence of Vms1, CAT-tailed polypeptides aggregate after import and sequester mitochondrial chaperones (e.g., Hsp78) and translation machinery. Genetic deletion, co-immunoprecipitation, ribosome fractionation, in vivo aggregation assay, mitochondrial import assay Cell High 29107329
2017 Mitochondrial targeting of yeast Vms1 (ANKZF1 ortholog) is mediated by a conserved mitochondrial targeting domain (MTD) that is held in an autoinhibited state through intramolecular binding to the Vms1 leucine-rich sequence (LRS). The oxidized sterol ergosterol peroxide binds the MTD competitively with the LRS to relieve autoinhibition and trigger Vms1 translocation to stressed mitochondria. 2.7 Å crystal structure, biochemical binding assay, sterol binding competition assay, live-cell fluorescence localization Molecular cell High 29149595
2013 Yeast Vms1 (ANKZF1 ortholog) mitochondrial targeting is negatively regulated by an intramolecular interaction between its N-terminal segment and the mitochondrial targeting domain (MTD). Vms1 is preferentially recruited to mitochondria under oxidative stress, as shown by laser-induced mitochondrial ROS generation. Truncation mutants, live-cell fluorescence imaging, laser-induced oxidative stress, biochemical binding assay Molecular biology of the cell Medium 23468520
2012 Yeast Vms1 (ANKZF1 ortholog) and its binding partner Cdc48 (but not Ufd1 or Ufd2) are required for degradation of Cdc13, a telomere-capping protein. Both autophagy and the proteasome contribute to Cdc13 turnover, and accumulation of Cdc13 in vms1Δ cells causes toxicity. Genetic deletion, protein degradation assay, epistasis with autophagy mutants The Journal of biological chemistry Medium 22718752
2014 The yeast Cdc48-Vms1 complex (ANKZF1 ortholog) is required for maintenance of 26S proteasome architecture. Loss of Vms1 leads to accumulation of unassembled 20S core particles and select 19S cap subunits, reduced 26S proteasome levels, accumulation of ubiquitinated proteins, and decreased viability in stationary phase. Vms1's support of proteasome assembly requires its interaction with Cdc48. Genetic deletion, native gel electrophoresis of proteasome complexes, ubiquitinated protein accumulation assay, viability assay The Biochemical journal Medium 24351022
2024 ANKZF1 knockdown in glioblastoma cells causes accumulation of CAT-tailed polypeptides in mitochondria, activating the mitochondrial unfolded protein response (UPRmt). Excess CAT-tails sequester mitochondrial chaperones HSP60 and mtHSP70, protease LONP1, and respiratory chain subunits ND1, Cytb, mtCO2, and ATP6, resulting in oxidative phosphorylation dysfunction, membrane potential impairment, and activation of the mitochondrial apoptotic pathway. siRNA knockdown, co-immunoprecipitation, mitochondrial fractionation, membrane potential assay, apoptosis assay, xenograft model Cancer letters Medium 38670305
2025 Human ANKZF1 participates in PINK1-Parkin-mediated mitophagy. ANKZF1 is recruited to damaged mitochondria together with Parkin during proteotoxic stress or membrane depolarization. ANKZF1 physically interacts with Parkin and LC3, and LIR motif 4 (residues 333–336) is required for ANKZF1–LC3 interaction. ANKZF1 knockout cells are defective in clearing stress-damaged mitochondria. ANKZF1 functions as a mitophagy adaptor bridging polyubiquitinated outer mitochondrial membrane proteins (via its UBA domain) and autophagosome receptor LC3 (via its LIR motif). ANKZF1 knockout, live-cell fluorescence imaging, co-immunoprecipitation, LIR mutagenesis, mitophagy flux assay Cell death discovery Medium 40730577
2026 The N-terminal 73 residues of human ANKZF1 negatively regulate its mitochondrial targeting by suppressing an internal matrix-targeting sequence-like sequence (iMTS-L) at residues 231–240. Deletion of the N-terminal segment causes structural rearrangement (shown by MD simulation) that exposes the 231–240 iMTS-L. Residues 231–324 constitute an independent mitochondrial signal that can target GFP to mitochondria when fused to its N-terminus. Truncation mutants, live-cell fluorescence localization, GFP-fusion targeting assay, molecular dynamics simulation The FEBS journal Medium 41920018
2024 ANKZF1 interacts with YWHAE (14-3-3ε) to competitively inhibit cytoplasmic retention of YAP1, thereby promoting YAP1 nuclear import and transcriptional activation of pro-lymphangiogenic factors in clear-cell renal cell carcinoma. NAT10-mediated ac4C modification of ANKZF1 mRNA upregulates ANKZF1 expression. Co-immunoprecipitation, immunofluorescence, site-directed mutagenesis, RNA immunoprecipitation, mass spectrometry Cancer communications Medium 38407929

Source papers

Stage 0 corpus · 16 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2017 Cytosolic Protein Vms1 Links Ribosome Quality Control to Mitochondrial and Cellular Homeostasis. Cell 163 29107329
2018 Vms1 and ANKZF1 peptidyl-tRNA hydrolases release nascent chains from stalled ribosomes. Nature 134 29632312
2018 Release of Ubiquitinated and Non-ubiquitinated Nascent Chains from Stalled Mammalian Ribosomal Complexes by ANKZF1 and Ptrh1. Molecular cell 96 30244831
2019 Structure and function of Vms1 and Arb1 in RQC and mitochondrial proteome homeostasis. Nature 78 31189955
2017 Sterol Oxidation Mediates Stress-Responsive Vms1 Translocation to Mitochondria. Molecular cell 35 29149595
2024 NAT10-mediated ac4C-modified ANKZF1 promotes tumor progression and lymphangiogenesis in clear-cell renal cell carcinoma by attenuating YWHAE-driven cytoplasmic retention of YAP1. Cancer communications (London, England) 29 38407929
2013 Intramolecular interactions control Vms1 translocation to damaged mitochondria. Molecular biology of the cell 26 23468520
2022 The expression changes of transcription factors including ANKZF1, LEF1, CASZ1, and ATOH1 as a predictor of survival rate in colorectal cancer: a large-scale analysis. Cancer cell international 15 36344988
2012 The Cdc48 protein and its cofactor Vms1 are involved in Cdc13 protein degradation. The Journal of biological chemistry 13 22718752
2024 ANKZF1 knockdown inhibits glioblastoma progression by promoting intramitochondrial protein aggregation through mitoRQC. Cancer letters 9 38670305
2014 The Cdc48-Vms1 complex maintains 26S proteasome architecture. The Biochemical journal 7 24351022
2024 Overexpression of ZNF169 promotes the growth and proliferation of colorectal cancer cells via the upregulation of ANKZF1. Oncology reports 5 38666541
2017 Vms1: A Cytosolic CAT-Tailing Antagonist to Protect Mitochondria. Trends in cell biology 4 29203248
2017 Vms1 Relieves a Mitochondrial Import Chokehold. Developmental cell 3 29112848
2025 ANKZF1 helps to eliminate stress-damaged mitochondria by LC3-mediated mitophagy. Cell death discovery 1 40730577
2026 The N-terminal segment of the human ANKZF1 negatively regulates its internal mitochondrial targeting signal to prevent localization to mitochondria. The FEBS journal 0 41920018