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Identification of BRCA2-DSS1 new partner HELZ

ABSTRACT: R-loops are dynamic three-stranded nucleic acid structures that regulate genome function but can threaten genome stability if not properly resolved. BRCA2, a key player in homologous recombination (HR), also regulates R-loops, though the mechanisms remain unclear. To uncover novel R-loop regulators, we employed a BioID-DSS1 proximity labeling system, leveraging DSS1’s stable interaction with BRCA2 to map its protein interaction network under DNA damage conditions. This approach identified HELZ, a putative RNA helicase, as a new BRCA2-DSS1 interactor. We found that HELZ functions as an RNA-specific R-loop resolvase, revealing a previously unrecognized BRCA2-HELZ axis in R-loop resolution. This work provides new insights into how BRCA2 safeguards genome integrity beyond its canonical role in HR.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Hela Cell

SUBMITTER: Wenjing Li

LAB HEAD: Weixing Zhao

PROVIDER: PXD066766 | Pride | 2025-12-30

REPOSITORIES: Pride

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			Action	DRS
	Experiment_MaxQuant_01_from_ZhaoW_021423_01.mgf	Mgf
	Experiment_MaxQuant_01_from_ZhaoW_021423_01.mzid	Mzid
	Experiment_MaxQuant_01_from_ZhaoW_101822_01.mgf	Mgf
	Experiment_MaxQuant_01_from_ZhaoW_101822_01.mzid	Mzid
	Experiment_MaxQuant_01_from_Zhao_051022_01.mgf	Mgf

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