Li L, Lu X, Peterson C, Legerski R
Department of Molecular Genetics, University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
Mutat Res. 1997 May 1;383(3):197-203. doi: 10.1016/s0921-8777(97)00002-5.
XP group C protein (XPC) and a human homologue of RAD23, HHR23B, have previously been shown to copurify in a tightly associated complex. Here, we show that XPC interacts in vivo, by means of the yeast two-hybrid system, with both HHR23B and a second homologue of RAD23, HHR23A. Domain mapping studies have revealed that both RAD23 homologues interact with XPC at the same highly conserved region in the C-terminal half of the protein. XPC mutants deleted within this domain and that are highly deficient in binding both RAD23 homologues are also highly defective in complementing XPC cells in vivo. Domain mapping studies have also identified a region in the N-terminal half of HHR23B that contains the XPC interactive site. This domain is highly conserved among HHR23B, HHR23A, and RAD23.
XP C组蛋白（XPC）和RAD23的人类同源物HHR23B先前已被证明能在一个紧密相关的复合物中共同纯化。在此，我们通过酵母双杂交系统表明，XPC在体内与HHR23B以及RAD23的第二个同源物HHR23A相互作用。结构域定位研究表明，两个RAD23同源物均在该蛋白C端一半的同一高度保守区域与XPC相互作用。在该结构域内缺失且与两个RAD23同源物结合高度缺陷的XPC突变体，在体内对XPC细胞进行互补时也存在高度缺陷。结构域定位研究还在HHR23B的N端一半区域鉴定出一个包含XPC相互作用位点的区域。该结构域在HHR23B、HHR23A和RAD23中高度保守。
