Proteins Binding to Cytosine-Rich Strand of Hypervariable Minisatellite DNA

与高变小卫星 DNA 富含胞嘧啶链结合的蛋白质

• 批准号: 63480123
• 负责人: KOMINAMI Ryo
• 金额: $ 4.67万
• 依托单位: Niigata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63480123/
• 关键词: Minisatellite; Recombination; DNA binding protein; 遺伝的組み換え; 染色体; 反復配列; ホットスポット

Two nuclear proteins, p35a and p35b, with a molecular weight of 35 kDa were detected that bound to hypervariable Pc-1 and Pc-2 minisatellites more efficiently than to genetically stable minisatellite homologues. Pc-1 and Pc-2 DNA probes used consisted of five and six repeats of GGCAG and AGGCAGG sequences, respectively. The binding required the presence of multiple of multiple repeat copies and of cytosine-rich single-stranded regions of the Pc-1 and Pc-2 sequences. p35a was detected in extracts from FM3A cells, mouse testis and liver, whereas p35b was found in the FM3A and liver extracts but not in the testis. Both proteins bound to the double-strands of Pc-1 and Pcー2 with single-strand regions, but only p35a was able to bind to their cytosine-rich single-strands. The protein-DNA complexes are assumed to result in forming a structure with single-stranded DNA loops in the DNA string of aminisatellite, which may enhance the ability of the minisatellite to undergo recombination.

两个核蛋白，p35 a和p35 b，分子量为35 kDa的检测，结合高变Pc-1和Pc-2小卫星比遗传稳定的小卫星同源物更有效。所用的Pc-1和Pc-2 DNA探针分别由5个和6个重复的GGCAG和AGGCAGG序列组成。这种结合需要存在多个重复拷贝和富含胞嘧啶的Pc-1和Pc-2序列的单链区域。p35 a在FM 3A细胞、小鼠睾丸和肝脏的提取物中检测到，而p35 b在FM 3A和肝脏提取物中发现，但在睾丸中没有。这两种蛋白质都以单链区域结合到Pc-1和Pc-2的双链上，但只有p35 a能够结合到它们富含胞嘧啶的单链上。蛋白质-DNA复合物被认为导致在小卫星的DNA链中形成具有单链DNA环的结构，这可能增强小卫星进行重组的能力。

项目成果

K. Mitani, R. Kominami et al.: "A GGCAGG motif in minisatellites affecting their germline instability." J. Biol. Chim.265. 15203-15210 (1990)

K. Mitani、R. Kominami 等人：“小卫星中的 GGCAGG 基序影响其种系不稳定性。”

Ryo Kominami: "A sensitive assay for detecting mutations resulting from unequal homologous recombination without phenotypic selection" Mutation Research. 243. 133-139 (1990)

Ryo Kominami：“一种灵敏的检测方法，用于检测由于不等同源重组而无需表型选择而产生的突变”突变研究。

K.Mitani,R.Kominami et al.: "A GGCAGG motif in minisatellites affecting their germline instability." J.Biol.Chem.265. 15203-15210 (1990)

K.Mitani,R.Kominami 等人：“小卫星中的 GGCAGG 基序影响其种系不稳定性。”