Department of Life Science, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea.
Genes Dev. 2010 Nov 1;24(21):2389-94. doi: 10.1101/gad.1974810.
The U2AF35-related protein Urp has been implicated previously in splicing of the major class of U2-type introns. Here we show that Urp is also required for splicing of the minor class of U12-type introns. Urp is recruited in an ATP-dependent fashion to the U12-type intron 3' splice site, where it promotes formation of spliceosomal complexes. Remarkably, Urp also contacts the 3' splice site of a U2-type intron, but in this case is specifically required for the second step of splicing. Thus, through recognition of a common splicing element, Urp facilitates distinct steps of U2- and U12-type intron splicing.
先前已有研究表明 U2AF35 相关蛋白 Urp 参与 U2 型内含子的剪接。本文发现 Urp 同样参与 U12 型内含子的剪接。UrP 以依赖于 ATP 的方式被招募到 U12 型内含子 3' 剪接位点,在该处促进剪接体复合物的形成。值得注意的是,UrP 还与 U2 型内含子的 3' 剪接位点结合,但在这种情况下,UrP 特异性地需要参与剪接的第二步。因此,通过识别共同的剪接元件,Urp 促进 U2 型和 U12 型内含子剪接的不同步骤。