Otsuki T, Furukawa Y, Ikeda K, Endo H, Yamashita T, Shinohara A, Iwamatsu A, Ozawa K, Liu J M
Department of Hematology, Jichi Medical School, Yakushiji 3311-1, Minamikawachi, Kawachi, Tochigi 329-0498, Japan.
Hum Mol Genet. 2001 Nov 1;10(23):2651-60. doi: 10.1093/hmg/10.23.2651.
Fanconi anemia (FA) is a genetic disorder that predisposes to hematopoietic failure, birth defects and cancer. We identified an interaction between the FA protein, FANCA and brm-related gene 1 (BRG1) product. BRG1 is a subunit of the SWI/SNF complex, which remodels chromatin structure through a DNA-dependent ATPase activity. FANCA was demonstrated to associate with the endogenous SWI/SNF complex. We also found a significant increase in the molecular chaperone, glucose-regulated protein 94 (GRP94) among BRG1-associated factors isolated from a FANCA-mutant cell line, which was not seen in either a normal control cell line or the mutant line complemented by wild-type FANCA. Despite this specific difference, FANCA did not appear to be absolutely required for in vitro chromatin remodeling. Finally, we demonstrated co-localization in the nucleus between transfected FANCA and BRG1. The physiological action of FANCA on the SWI/SNF complex remains to be clarified, but our work suggests that FANCA may recruit the SWI/SNF complex to target genes, thereby enabling coupled nuclear functions such as transcription and DNA repair.
范可尼贫血(FA)是一种遗传性疾病,易导致造血功能衰竭、出生缺陷和癌症。我们发现了FA蛋白FANCA与brm相关基因1(BRG1)产物之间的相互作用。BRG1是SWI/SNF复合物的一个亚基,它通过依赖于DNA的ATP酶活性重塑染色质结构。已证明FANCA与内源性SWI/SNF复合物相关联。我们还发现,从FANCA突变细胞系中分离出的与BRG1相关的因子中,分子伴侣葡萄糖调节蛋白94(GRP94)显著增加,而在正常对照细胞系或由野生型FANCA互补的突变细胞系中均未观察到这种情况。尽管存在这种特定差异,但FANCA似乎并非体外染色质重塑绝对必需的。最后,我们证明了转染的FANCA和BRG1在细胞核中共定位。FANCA对SWI/SNF复合物的生理作用仍有待阐明,但我们的研究表明,FANCA可能将SWI/SNF复合物招募到靶基因,从而实现转录和DNA修复等相关的核功能。