范可尼贫血患者FANCA突变子的构建及其功能  

Construction of FANCA mutant protein from Fanconi anemia patient and analysis of its function

作　　者：陈飞[1] 张克俭[1] 左学兰[1] 曾宪昌[1] 

机构地区：[1]武汉大学中南医院血液科,430071

出　　处：《中华血液学杂志》2007年第11期741-744,共4页Chinese Journal of Hematology

摘　　要：目的研究范可尼贫血(FA)患者 FANCA 蛋白的表达及其突变子的功能。方法用3例来源于 FA-A 型患者的外周血淋巴细胞建立的细胞系作为研究对象,分别提取其细胞总蛋白、细胞胞质蛋白和细胞核蛋白,用 Western blot 法分析 FANCA 蛋白的表达及其在细胞胞质和细胞核内的分布,对1例有 FANCA 截短型蛋白表达的 FA 患者,构建了质粒突变子并用哺乳动物细胞双杂交方法检测 FANCA 基因突变子(外显子5缺失)与 FANCG 蛋白的相互作用。结果用兔抗人抗体检测时,3例 FA-A 患者均无 FANCA 蛋白的表达,而用鼠抗人抗体检测时,有1例患者可检测到截短型 FANCA 蛋白表达,但此截短型 FANCA 蛋白不能从细胞胞质转运到细胞核,也不能在哺乳动物细胞双杂交系统中与 FANCG 蛋白相互作用。结论 3例 FA-A 患者中,2例无 FANCA 蛋白表达,1例可表达截短型FANCA 蛋白,但无正常 FANCA 蛋白功能,进一步证实其 FANCA 基因突变为致病性病理突变,FANCA基因外显子5参与了与 FANCG 的相互作用。Objective To study FANCA protein expression in Fanconi anemia patient＇ s （FA） cells and explore its function. Methods FANCA protein expression was analyzed in 3 lymphoblast ceU lines de- rived from 3 cases of type A FA （FA-A） patients using Western blot. Nucleus and cytoplasm localization of FANCA protein was analyzed in one case of FA-A which contained a truncated FANCA （exon 5 deletion）. The FANCA mutant was constructed from the same patient and its interaction with FANCG was evaluated by mammalian two-hybrid （M2H） assay. Results FANCA protein was not detected in the 3 FA-A patients by rabbit anti-human MoAb, but a truncated FANCA protein was detected in 1 of them by mouse anti-human MoAb. The truncated FANCA could not transport from cytoplasm into nucleus. The disease-associated FANCA mutant was defective in binding to FANCG in M2H system. Conclusions FANCA proteins are defective in the 3 FA-A patients. Disfunction of disease-associated FANCA mutant proved to be the pathogenic mutations in FANCA gene. Exon 5 of FANCA gene was involved in the interaction between FANCA and FANCG.

关 键 词：范可尼贫血 基因 FANCA 突变子 

分 类 号：Q987[生物学—遗传学]