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A human BRCA2 complex containing a structural DNA binding component influences cell cycle progression.

L Y Marmorstein·A V Kinev·G K Chan·D A Bochar·H Beniya·J A Epstein·T J Yen·R Shiekhattar
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Abstract

Germline mutations of the human BRCA2 gene confer susceptibility to breast cancer. Although the function of the BRCA2 protein remains to be determined, murine cells homozygous for BRCA2 inactivation display chromosomal aberrations. We have isolated a 2 MDa BRCA2-containing complex and identified a structural DNA binding component, designated as BRCA2-Associated Factor 35 (BRAF35). BRAF35 contains a nonspecific DNA binding HMG domain and a kinesin-like coiled coil domain. Similar to BRCA2, BRAF35 mRNA expression levels in mouse embryos are highest in proliferating tissues with high mitotic index. Strikingly, nuclear staining revealed a close association of BRAF35/BRCA2 complex with condensed chromatin coincident with histone H3 phosphorylation. Importantly, antibody microinjection experiments suggest a role for BRCA2/BRAF35 complex in modulation of cell cycle progression.

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Amino Acid SequenceAnimalsAntibodiesBRCA2 ProteinBreast NeoplasmsCell FractionationCell NucleusChromatinChromosomesDNA-Binding ProteinsEmbryo, MammalianFemaleHeLa CellsHigh Mobility Group ProteinsHumansIn Situ HybridizationMiceMicroinjectionsMitosisMolecular Sequence DataNeoplasm ProteinsNucleic Acid ConformationOvarian NeoplasmsPrecipitin TestsProtein Structure, TertiaryTranscription FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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L Y Marmorstein, A V Kinev, G K Chan, D A Bochar, H Beniya, J A Epstein, T J Yen, R Shiekhattar. 2001-01-26. A human BRCA2 complex containing a structural DNA binding component influences cell cycle progression.. https://doi.org/10.1016/s0092-8674(01)00209-4

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