Svejstrup J Q, Wang Z, Feaver W J, Wu X, Bushnell D A, Donahue T F, Friedberg E C, Kornberg R D
Department of Structural Biology, Stanford University School of Medicine, California 94305-5400.
Cell. 1995 Jan 13;80(1):21-8. doi: 10.1016/0092-8674(95)90447-6.
Yeast TFIIH that is active in transcription can be dissociated into three components: a 5-subunit core, the SSL2 gene product, and a complex of 47 kDa, 45 kDa, and 33 kDa polypeptides that possesses protein kinase activity directed towards the C-terminal repeat domain of RNA polymerase II. These three components can reconstitute fully functional TFIIH, and all three are required for transcription in vitro. By contrast, TFIIH that is highly active in nucleotide excision repair (NER) lacks the kinase complex and instead contains the products of all other genes known to be required for NER in yeast: RAD1, RAD2, RAD4, RAD10, and RAD14. This repairosome is not active in reconstituted transcription in vitro and is significantly more active than any of the constituent polypeptides in correcting defective repair in extracts from strains mutated in NER genes.
在转录过程中具有活性的酵母TFIIH可解离为三个组分：一个由5个亚基组成的核心、SSL2基因产物，以及一个由47 kDa、45 kDa和33 kDa多肽组成的复合体，该复合体具有针对RNA聚合酶II C末端重复结构域的蛋白激酶活性。这三个组分可重新组装成功能完全的TFIIH，且所有这三个组分都是体外转录所必需的。相比之下，在核苷酸切除修复（NER）中具有高活性的TFIIH缺乏激酶复合体，而是包含酵母中NER所需的所有其他已知基因的产物：RAD1、RAD2、RAD4、RAD10和RAD14。这种修复体在体外重构转录中无活性，并且在纠正NER基因突变菌株提取物中的缺陷修复方面，其活性明显高于任何组成多肽。
