Institute of Genetics, University of Braunschweig TU, Spielmannstr. 7, 38106 Braunschweig, Germany.
Nucleic Acids Res. 2010 Mar;38(5):1610-22. doi: 10.1093/nar/gkp1155. Epub 2009 Dec 9.
The spliceosomal protein Prp1 (Prp6/U5-102 K) is necessary for the integrity of pre-catalytic spliceosomal complexes. We have identified a novel regulatory function for Prp1. Expression of mutations in the N-terminus of Prp1 leads to the accumulation of pre-catalytic spliceosomal complexes containing the five snRNAs U1, U2, U5 and U4/U6 and pre-mRNAs. The mutations in the N-terminus, which prevent splicing to occur, include in vitro and in vivo identified phosphorylation sites of Prp4 kinase. These sites are highly conserved in the human ortholog U5-102 K. The results presented here demonstrate that structural integrity of the N-terminus is required to mediate a splicing event, but is not necessary for the assembly of spliceosomes.
剪接体蛋白 Prp1(Prp6/U5-102 K)对于前催化剪接体复合物的完整性是必需的。我们已经确定了 Prp1 的一个新的调节功能。表达 Prp1 氨基端突变会导致含有五个 snRNA U1、U2、U5 和 U4/U6 以及前体 mRNA 的前催化剪接体复合物的积累。这些突变阻止剪接的发生,包括体外和体内鉴定的 Prp4 激酶的磷酸化位点。这些位点在人类同源物 U5-102 K 中高度保守。这里呈现的结果表明,N 端的结构完整性对于介导剪接事件是必需的,但对于剪接体的组装不是必需的。