| 2019 |
HROB (C17orf53) is an OB-fold-containing protein that recruits the MCM8-MCM9 helicase to sites of DNA damage to promote HR-associated DNA synthesis downstream of RAD51. Mice with targeted Hrob mutations are infertile due to germ cell depletion consistent with prophase I meiotic arrest. The HROB-MCM8-MCM9 pathway acts redundantly with the HELQ helicase; cells lacking both HROB and HELQ have severely impaired HR. |
Targeted mouse mutagenesis, genetic epistasis (HROB/HELQ double KO), cellular HR assays, focus formation/recruitment assays |
Genes & development |
High |
31467087
|
| 2020 |
HROB (MCM8IP/C17orf53) binds ssDNA and directly associates with both the MCM8-9 helicase complex and RPA1. HROB stimulates the helicase activity of MCM8-9 in vitro, and its interactions with MCM8-9 and RPA are required for HR (specifically long-tract gene conversion downstream of RAD51 loading), replication fork progression, and cellular viability after crosslinking agent treatment. |
In vitro helicase activity assay with purified proteins, Co-IP/pulldown (HROB–MCM8-9 and HROB–RPA1), HR reporter assays, crosslinker/PARP inhibitor sensitivity assays in MCM8IP-deficient cells |
Nature communications |
High |
32528060
|
| 2020 |
C17orf53/HROB is a ssDNA- and RPA-binding protein required for interstrand crosslink (ICL) repair and efficient DNA replication; its loss leads to hypersensitivity to ATR inhibition and pronounced ICL repair defects. HROB works together with MCM8/9 to promote cell survival after ICL lesions. |
Genome-wide ATR-inhibitor fitness screen, multi-omics interaction studies, ssDNA/RPA-binding assays, cellular ICL sensitivity assays, DNA replication rate measurement in C17orf53 KO cells |
DNA repair |
Medium |
32853826
|
| 2024 |
Biochemical and structural analysis defined the HROB–MCM8-9 interaction interface: HROB makes transient contacts with both MCM8 and MCM9 subunits and binds the MCM8-9 heterodimer with highest affinity. MCM8-9-HROB preferentially binds and unwinds branched DNA structures with low processivity. MCM8-9 assembles into a hexamer from dimers on DNA in the presence of ATP via two alternating interfaces (one stable/obligate heterodimer, one labile mediating hexamer assembly). HROB does not affect ring/hexamer formation but promotes DNA unwinding downstream of loading, likely by coordinating ATP hydrolysis with translocation. The ATPase site at the labile interface contributes disproportionately more to unwinding. |
Molecular modeling, biochemistry (ATPase assays, helicase assays, binding assays), single-molecule experiments (unwinding processivity), mutational analysis of interfaces |
Nature communications |
High |
38678026
|
| 2024 |
HROB is a nuclear protein whose level peaks in S phase and is downregulated in quiescence, co-regulated with DNA replication factors. Flow cytometry FRET assays detected associations between HROB and proteins of the DNA replication machinery. Ectopic overexpression of HROB caused an almost complete shutdown of DNA replication. |
Flow cytometry FRET (protein–protein association), cell cycle analysis, ectopic overexpression with DNA replication readout, structural prediction/homology analysis |
Genes |
Low |
39766854
|
| 2026 |
Cryo-EM structures of MCM8/9 with DNA, HROB, and ATP analogs revealed that DNA binding induces a rotational rearrangement between N-terminal DNA-binding and C-terminal AAA+ ATPase domains, reorganizing DNA-binding loops into a staircase configuration. HROB associates with both halves of the heterohexamer and drives a similar rotation prior to DNA binding, localizing MCM8/9 to crosslink damage sites and enabling unwinding, providing a unified mechanistic model for MCM8/9 helicase activation by HROB. |
Cryo-electron microscopy (cryo-EM) with ATP analogs and DNA substrates, structural analysis of conformational states |
bioRxivpreprint |
Medium |
42094346
|
| 2025 |
HROB is required for MCM8/9 focus formation at ICL damage sites (functional activation context), but HROB is not required for FANCD2 binding to MCM8/9. MCM8/9 physically interacts with FANCD2 through its core domain independently of DNA, and FANCD2 acts upstream of MCM9 recruitment to ICL-induced nuclear foci downstream of FANCD2 monoubiquitination. MCM8/9 and FANCD2 are epistatic (combined loss does not cause additive DNA damage), placing MCM8/9 as a downstream effector of the FA pathway. |
Co-immunoprecipitation, immunofluorescence focus assays, genetic epistasis (double KO γH2AX and survival assays), MCM8/9 KO cell lines |
bioRxivpreprint |
Medium |
bio_10.1101_2025.08.07.669127
|
| 2025 |
HROB suppresses lung adenocarcinoma cell proliferation by interacting with ZC3HC1 and reducing its phosphorylation at Ser354, which facilitates K27-linked ubiquitination of CCNB1 and its proteasomal degradation, impairing the G2-to-M phase transition. |
Co-immunoprecipitation (HROB–ZC3HC1 interaction), phosphorylation analysis, ubiquitination assay, proteasomal degradation assay, cell proliferation/tumor growth assays with KO/overexpression |
Cancer science |
Low |
40654113
|