Molecular Mechanisms of DNA Damage Recoguition and Repair

DNA损伤识别与修复的分子机制

• 批准号: 08407072
• 负责人: HANAOKA Fumio
• 金额: $ 24.06万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08407072/
• 关键词: DNA repair; NER; xeroderma pigmentosum; XPC protein; Vpr protein; HHR23B protein; 26S proteasome; S5a protein; 修復; ヌクレオチド除去修復; RNAポリメラーゼII; XPE蛋白質; ヌクレチオド除去修復; TFIIH; XPG蛋白質; p53蛋白質

We previously isolated a protein complex which biochemically corrects the defect of XP-C cell extracts in nucleotide excision repair (NER) in vitro. In the present study, we have analyzed the functions of the protein complex, XPC/HHR23B, in NER in mammalian cells and obtained the following results.1) In mouse cells, there are homologues of human XPC/HHR23B and another RAD23 homologue, HHR23A.They have quite high homologies with each other.2) We found most of XPC, HHR23B and HHR23A in nucleus. They do not make a tight complex with other NER proteins.3) HHR23B stimulates the NER activity of XPC protein in vitro.4) HHR23A protein makes a complex with HIV-1 Vpr protein and affects the cell cycle progression.5) A very limited region of HHR23B is necessary and sufficient for XPC binding as well as the stimulation of NER activity of XPC.6) HHR23A could reconstitute a physical complex with XPC and stimulate the in vitro repair activity in place of HHR23B.7) XPC/HHR23B complex works as the earliest damage detector to initiate global genome repair subpathway of NER.8) We found that a component of 26S proteasome, S5a, associates with HHR23B in yeast two-hybrid system as well as in crude cell extracts.

我们先前分离出一种蛋白复合物，该蛋白复合物在体外以生物化学方式纠正XP-C细胞提取物在核苷酸切除修复（NER）中的缺陷。本研究对XPC/HHR 23 B蛋白复合物在哺乳动物细胞NER中的功能进行了分析，得到以下结果：1）在小鼠细胞中，存在人XPC/HHR 23 B和另一个RAD 23同源物HHR 23 A的同源物，它们之间具有很高的同源性; 2）XPC、HHR 23 B和HHR 23 A大部分存在于细胞核中。HHR 23 B蛋白在体外刺激XPC蛋白的NER活性; HHR 23 A蛋白与HIV-1 Vpr蛋白形成复合物并影响细胞周期进程; HHR 23 B的一个非常有限的区域对于XPC结合以及刺激XPC的NER活性是必需的和足够的。HHR 23 A可以与XPC重组一个物理复合物，并刺激HHR 23 B的体外修复活性。7）XPC/HHR 23 B复合物作为最早的损伤检测器启动了NER的全基因组修复亚途径。8）我们发现26 S蛋白酶体的一个组分S5 a，在酵母双杂交系统中以及在粗细胞提取物中与HHR 23 B缔合。

项目成果

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Carrier,F.：“gadd 基因反应中不同激酶介导途径的证据。”

Mizuno,T.: "The second largest subunit of the mouse DNA polymerased α-primase complex facilitates both the production and nudear translocation of the catalytic subunit of DNA polymerased." Mol.Cell.Biol.18. 3552-3562 (1998)

Mizuno, T.：“小鼠 DNA 聚合酶 α-引物酶复合物的第二大亚基促进 DNA 聚合酶催化亚基的产生和核易位。”Mol.Cell.Biol.18 (1998)。

Witheres-Ward, E.S., Jowett, J.B., Stewart, S.A., Xie, Y.M., Garfinkel, A., Shibagaki, Y., Chow, S.A., Shah, N., Hanaoka, F., Sawitz, D,G., Armstrong, R.W., Souza, L.M., and Chen, I.S.: "Human immunodeficiency virus type 1 Vpr interacts with HHR23A,a cell

Witheres-Ward, E.S.、Jowett, J.B.、Stewart, S.A.、Xie, Y.M.、Garfinkel, A.、Shibagaki, Y.、Chow, S.A.、Shah, N.、Hanaoka, F.、Sawitz, D,G.、阿姆斯特朗

van der Spek, P.J.: "XPC and human homologs of RAD23:intracellular localization and relationship to other nucleotide excision repair complexes." Nucl.Acids Res.24. 2551-2559 (1996)

van der Spek, P.J.：“XPC 和 RAD23 的人类同源物：细胞内定位以及与其他核苷酸切除修复复合物的关系。”

Masutani, C.: "Identification and charactarization of XPC-biading domain of hHR23B" Mol.Cell.Biol.17. 6915-6923 (1997)

Masutani, C.：“hHR23B XPC 偏置结构域的鉴定和表征”Mol.Cell.Biol.17。