| 2007 |
RAD51AP1 binds both dsDNA and D-loop structures, and stimulates the RAD51-mediated D-loop reaction only when able to physically interact with RAD51; epistasis experiments placed RAD51AP1 in the same pathway as XRCC3, and biochemical/cytological data showed it acts subsequent to RAD51-ssDNA nucleoprotein filament assembly. |
In vitro D-loop assay with purified proteins, DNA-binding assays, RNAi knockdown + epistasis with XRCC3, cytological RAD51 focus analysis |
Molecular cell |
High |
17996711
|
| 2007 |
RAD51AP1 selectively binds branched DNA structures (obligatory intermediates in joint molecule formation) and physically contacts RAD51 to stimulate joint molecule/D-loop formation; both activities together confer its ability to promote homologous recombination. |
Purified protein DNA-binding assays with branched vs. linear substrates, in vitro joint molecule formation assay, Co-IP/pulldown with RAD51 |
Molecular cell |
High |
17996710
|
| 2011 |
RAD51AP1 physically associates with the meiosis-specific recombinase DMC1 and stimulates DMC1-mediated D-loop reaction by enhancing the ability of the DMC1 presynaptic filament to capture duplex DNA and assemble the synaptic complex; distinct epitopes in RAD51AP1 mediate RAD51 vs. DMC1 interactions; RAD51AP1 colocalizes with DMC1 foci in mouse spermatocytes. |
Pulldown/Co-IP of RAD51AP1-DMC1, in vitro D-loop assay with purified DMC1, immunofluorescence co-localization in mouse spermatocytes, truncation/point mutation mapping |
Proceedings of the National Academy of Sciences of the United States of America |
High |
21307306
|
| 2011 |
A conserved WVPP motif in RAD51AP1 is critical for DMC1 interaction but dispensable for RAD51 association, defining two distinct binding interfaces on RAD51AP1 for its two recombinase partners. |
Truncation and point mutation analysis of RAD51AP1, pulldown assays |
The Journal of biological chemistry |
High |
21903585
|
| 2012 |
RAD51AP1 harbors two distinct DNA-binding domains, both required for maximal stimulation of RAD51 recombinase activity under physiological conditions; mutants impaired in either domain are non-functional in cells. |
Domain mapping via truncations and point mutations, in vitro DNA-binding assays (EMSA), in vitro D-loop assays, cellular complementation assays |
The Journal of biological chemistry |
High |
22375013
|
| 2006 |
RAD51AP1 (PIR51/Pir51) interacts with RAD51 through a conserved C-terminal motif; the same structural motif is shared with RAD51AP2, and truncations/point mutations in both proteins defined the minimal RAD51-binding region (~40 amino acids). |
Yeast two-hybrid, co-immunoprecipitation in HEK293 cells, truncation/point mutation analysis |
Nucleic acids research |
Medium |
16990250
|
| 2014 |
RAD51AP1 is required to maintain wild-type replication fork progression speed; RAD51AP1-deficient vertebrate cells (human and chicken DT40 knockouts) show slowed replication fork elongation, increased new-origin firing, and delayed resolution (but not impaired formation) of DNA damage-induced RAD51 foci. |
Targeted gene knockout in DT40 cells, DNA fiber assay (replication fork speed), RAD51 focus kinetics by immunofluorescence, clonogenic survival assays |
DNA repair |
High |
25288561
|
| 2015 |
NUCKS1, a paralog of RAD51AP1, shares extensive sequence homology and the same DNA-binding preference as RAD51AP1 but binds DNA with reduced affinity; NUCKS1 knockdown phenocopies RAD51AP1 knockdown (impaired HR, increased MMC sensitivity, chromatid breaks, slowed replication forks). |
Sequence homology analysis, in vitro DNA-binding assays, siRNA knockdown, HR reporter assay, DNA fiber assay, cytogenetics |
Nucleic acids research |
Medium |
26323318
|
| 2016 |
RAD51AP1 forms a dimeric complex with UAF1 (mediated by SUMO-like domains in UAF1 and a SUMO-interacting motif in RAD51AP1) and a trimeric complex with RAD51 through RAD51AP1; UAF1 enhances RAD51-mediated homologous DNA pairing in a RAD51AP1-dependent but USP1-independent manner; the RAD51AP1-UAF1 complex cooperates with RAD51 to assemble the synaptic complex. |
Purified protein complex reconstitution, in vitro D-loop/synaptic complex assays, mutagenesis of SUMO-interacting motif, cellular complementation with interaction-deficient mutants |
Cell reports |
High |
27239033
|
| 2016 |
UAF1 mediates interaction between USP1 and RAD51AP1; USP1 or UAF1 depletion decreases RAD51AP1 stability; UAF1-interaction-deficient RAD51AP1 mutants show persistent RAD51 foci after DNA damage and increased chromosomal aberrations, indicating USP1-UAF1 regulates a late step in HR via RAD51AP1. |
Proteomic pulldown/mass spectrometry of UAF1 interactors, Co-IP, protein stability assays, RAD51 focus kinetics, chromosomal aberration analysis with interaction-deficient point mutants |
Cell cycle (Georgetown, Tex.) |
Medium |
27463890
|
| 2019 |
Efficient FANCD2 deubiquitination by the USP1-UAF1 complex is DNA-dependent and requires DNA binding by UAF1; RAD51AP1's DNA-binding activity can substitute for UAF1's DNA-binding activity to support FANCD2 deubiquitination in a reconstituted biochemical system and in cells, revealing that the USP1-UAF1-RAD51AP1 complex participates in the Fanconi anemia pathway through DNA-dependent FANCD2 deubiquitination. |
Reconstituted biochemical deubiquitination assays with purified USP1-UAF1-RAD51AP1, DNA-binding mutants, cellular FANCD2 ubiquitination assays |
Nature communications |
High |
31253762
|
| 2019 |
RAD51AP1 is essential for ALT-mediated telomere elongation; its disruption causes generational telomere shortening in ALT+ cells through loss of both RAD51-dependent HR and RAD52-POLD3-dependent break-induced DNA synthesis; RAD51AP1 protein levels in ALT+ cells are elevated by MMS21-associated SUMOylation, and mutation of a single SUMO-targeted lysine perturbs telomere dynamics. |
RAD51AP1 knockout in ALT+ cells, telomere length assays, cGAS-STING activation readout, SUMOylation assays with MMS21, site-directed mutagenesis of SUMO-targeted lysine |
Molecular cell |
High |
31400850
|
| 2021 |
RAD51AP1 binds nucleosome core particles (NCPs) through its C-terminal DNA-binding domain; it can promote duplex DNA capture and joint molecule formation with NCP and chromatinized template DNA in vitro, suggesting it assists RAD51-mediated homology search in chromatin by anchoring the nucleosomal DNA template to the RAD51-ssDNA filament. |
In vitro NCP-binding assay (EMSA), pulldown of RAD51AP1 with histone octamer, in vitro D-loop assay with chromatinized template, C-terminal deletion mutants |
The Journal of biological chemistry |
High |
34058198
|
| 2022 |
RAD51AP1 interacts with TERRA RNA and promotes telomeric R-loop formation; RAD51AP1 depletion reduces R-loop formation at telomere DNA breaks; RAD51AP1-mediated TERRA R-loops also generate G-quadruplexes (G4s) that persist after R-loop resolution, enabling D-loop formation without RAD52 and thus driving a RAD52-independent ALT pathway. |
In vitro R-loop formation assay with TERRA and RAD51AP1, telomere-specific R-loop immunoprecipitation (DRIP), G4 stabilization experiments, RAD51AP1 and RAD52 KO cells, BIR activity assays |
Molecular cell |
High |
36265486
|
| 2022 |
RAD51AP1 regulates TERRA R-loop homeostasis at ALT telomeres; its interaction with TERRA and telomeric chromatin suppresses transcription-replication collisions during ALT-HDR; this non-canonical function requires RAD51AP1's intrinsic SUMO-SIM regulatory axis. |
Proteomic analysis, TERRA RNA immunoprecipitation, R-loop immunoprecipitation at telomeres, RAD51AP1 depletion with SUMO-SIM mutants, replication-transcription collision assays |
Molecular cell |
High |
36265488
|
| 2022 |
RAD51AP1 and RAD54L operate in two distinct parallel sub-pathways downstream of RAD51 in homologous recombination; simultaneous deletion of both genes further sensitizes cancer cells to PARP inhibitors, mitomycin C, and hydroxyurea beyond single deletions, establishing a synthetic interaction. |
Double-gene deletion in human cancer cell lines, clonogenic survival assays with olaparib/MMC/HU, epistasis analysis |
Frontiers in cell and developmental biology |
Medium |
35652094
|
| 2024 |
RAD51AP1 associates with pre-rRNA; both N- and C-termini of RAD51AP1 bind pre-rRNA; pre-rRNA co-localizes with RAD51AP1 at DSBs and facilitates RAD51AP1 recruitment to DSBs; inhibition of RNA Pol I (pre-rRNA synthesis) suppresses RAD51AP1 DSB recruitment and HR; RAD51AP1 forms liquid-liquid phase separation in the presence of pre-rRNA in vitro, potentially underlying foci formation. |
RNA immunoprecipitation, co-localization at DSBs, RNA Pol I inhibitor treatment, LLPS assay in vitro with purified proteins, HR reporter assay |
The Journal of biological chemistry |
Medium |
38403248
|
| 2025 |
RAD51AP1 activity in homology-directed repair is regulated by CDK2-mediated phosphorylation at S277/282; phospho-ablating S277/282A mutations increase DNA/nucleosome binding and D-loop stimulation in vitro but fail to rescue RAD51AP1 deficiency in cells, whereas phosphomimetic S277/282D fully rescues; this indicates phosphorylation ensures dynamic RAD51AP1 engagement across consecutive HDR steps. |
Site-directed mutagenesis (S277/282A and S277/282D), in vitro D-loop assay, EMSA with ssDNA/dsDNA/NCP, cellular toxicity and DNA replication assays with mutant rescue, CDK2 kinase assay |
The Journal of biological chemistry |
High |
41534830
|
| 2025 |
Cryo-EM/structural analysis reveals RAD51AP1 possesses at least three RAD51-binding sites that span two adjacent RAD51 protomers; RAD51AP1 stabilizes the RAD51 N-terminal domain and protomer interface within filaments, promotes RAD51-ssDNA filament nucleation, stabilization, and strand exchange; ATP hydrolysis to ADP causes RAD51 filament expansion and reduces RAD51-DNA binding. |
Cryo-EM structural analysis of RAD51-ssDNA filaments with/without RAD51AP1, biochemical strand exchange assays, mutagenesis of binding sites, structural analysis of Mg2+-ATP vs. Mg2+-ADP states |
Proceedings of the National Academy of Sciences of the United States of America |
High |
41337480
|
| 2006 |
RAD51AP1 (Pir51) is a nuclear protein whose expression is cell-cycle regulated similarly to RAD51; siRNA depletion sensitizes cells to mitomycin C and increases double-strand breaks in metaphase spreads without reducing HR repair efficiency, placing RAD51AP1 in a RAD51-associated pathway that specifically responds to DNA crosslink damage. |
siRNA knockdown, clonogenic survival assays, metaphase chromosome spread analysis, HR reporter assay (I-SceI) |
Mutation research |
Medium |
16920159
|
| 2025 |
TERRA R-loop formation at telomeres requires non-redundant functions of both RAD51 and RAD51AP1; TERRA R-loops interfere with semiconservative DNA replication, promoting break-induced replication (BIR) for telomere maintenance. |
TERRA overexpression system, DRIP-seq, RAD51AP1 depletion, BIR activity assay, telomere maintenance assays |
bioRxivpreprint |
Medium |
bio_10.1101_2025.01.09.632133
|