该基因属于基因的剪接因子SR家族。u2辅助因子包括一个大的和一个小的亚单位，是一种非snrnp蛋白，它是u2 snrnp结合到pre-mrna分支位点所必需的。该基因编码小亚单位，通过直接介导大亚单位和与增强子结合的蛋白质之间的相互作用，在组成和增强子依赖的RNA剪接中起关键作用。另外，还发现了编码不同亚型的剪接转录变体。
This gene belongs to the splicing factor SR family of genes. U2 auxiliary factor, comprising a large and a small subunit, is a non-snRNP protein required for the binding of U2 snRNP to the pre-mRNA branch site. This gene encodes the small subunit which plays a critical role in both constitutive and enhancer-dependent RNA splicing by directly mediating interactions between the large subunit and proteins bound to the enhancers. Alternatively spliced transcript variants encoding different isoforms have been identified.