TBP-TAF（II）230复合物的溶液结构：TBP解开的TATA盒小沟表面的蛋白质模拟。

Solution structure of a TBP-TAF(II)230 complex: protein mimicry of the minor groove surface of the TATA box unwound by TBP.

作者信息

Liu D, Ishima R, Tong K I, Bagby S, Kokubo T, Muhandiram D R, Kay L E, Nakatani Y, Ikura M

机构信息

Department of Medical Biophysics, University of Toronto, Ontario, Canada.

出版信息

Cell. 1998 Sep 4;94(5):573-83. doi: 10.1016/s0092-8674(00)81599-8.

DOI:10.1016/s0092-8674(00)81599-8

PMID:9741622

Abstract

General transcription factor TFIID consists of TATA box-binding protein (TBP) and TBP-associated factors (TAF(II)s), which together play a central role in both positive and negative regulation of transcription. The N-terminal region of the 230 kDa Drosophila TAF(II) (dTAF(II)230) binds directly to TBP and inhibits TBP binding to the TATA box. We report here the solution structure of the complex formed by dTAF(II)230 N-terminal region (residues 11-77) and TBP. dTAF(II)230(11-77) comprises three alpha helices and a beta hairpin, forming a core that occupies the concave DNA-binding surface of TBP. The TBP-binding surface of dTAF(II)230 markedly resembles the minor groove surface of the partially unwound TATA box in the TBP-TATA complex. This protein mimicry of the TATA element surface provides the structural basis of the mechanism by which dTAF(II)230 negatively controls the TATA box-binding activity within the TFIID complex.

摘要

通用转录因子TFIID由TATA盒结合蛋白（TBP）和TBP相关因子（TAF（II）s）组成，它们在转录的正调控和负调控中都起着核心作用。230 kDa果蝇TAF（II）（dTAF（II）230）的N端区域直接与TBP结合，并抑制TBP与TATA盒的结合。我们在此报告由dTAF（II）230 N端区域（第11至77位氨基酸残基）和TBP形成的复合物的溶液结构。dTAF（II）230（11 - 77）包含三个α螺旋和一个β发夹结构，形成一个核心，占据TBP的凹面DNA结合表面。dTAF（II）230的TBP结合表面与TBP - TATA复合物中部分解旋的TATA盒的小沟表面显著相似。这种对TATA元件表面的蛋白质模拟为dTAF（II）230在TFIID复合物中负调控TATA盒结合活性的机制提供了结构基础。