SF3B1

This gene encodes subunit 1 of the splicing factor 3b protein complex. Splicing factor 3b, together with splicing factor 3a and a 12S RNA unit, forms the U2 small nuclear ribonucleoproteins complex (U2 snRNP). The splicing factor 3b/3a complex binds pre-mRNA upstream of the intron's branch site in a sequence independent manner and may anchor the U2 snRNP to the pre-mRNA. Splicing factor 3b is also a component of the minor U12-type spliceosome. The carboxy-terminal two-thirds of subunit 1 have 22 non-identical, tandem HEAT repeats that form rod-like, helical structures. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008]

本基因编码剪接因子3b蛋白复合物的亚基1。剪接因子3b与剪接因子3a及一个12S核糖核酸单元共同组成U2小核糖核蛋白复合物（U2 snRNP）。该复合物以序列非依赖性方式在剪接位点上游与前mRNA结合，并可能将U2 snRNP锚定至前mRNA。剪接因子3b亦为小U12型剪接体的组成部分。亚基1的羧基端三分之二区域含有22个非同源、串联的HEAT重复序列，这些序列形成棒状、螺旋结构。可变剪接导致产生多种转录本变体，编码不同的异构体。[由RefSeq提供，2008年7月]