Plass Mireya, Agirre Eneritz, Reyes Diana, Camara Francisco, Eyras Eduardo
Computational Genomics Group, Universitat Pompeu Fabra, PRBB, Dr. Aiguader 88 E08003, Barcelona, Spain.
Trends Genet. 2008 Dec;24(12):590-4. doi: 10.1016/j.tig.2008.10.004. Epub 2008 Nov 5.
Serine-arginine-rich (SR) proteins are essential for splicing in metazoans but are absent in yeast. By contrast, many fungi have SR protein homologs with variable arginine-rich regions analogous to the arginine-serine-rich (RS) domain in metazoans. The density of RS repeats in these regions correlates with the conservation of the branch site signal, providing evidence for an ancestral origin of SR proteins and indicating that the SR proteins and the branch site co-evolved.
富含丝氨酸-精氨酸（SR）的蛋白质对于后生动物的剪接至关重要，但在酵母中不存在。相比之下，许多真菌具有SR蛋白同源物，其富含精氨酸的区域可变，类似于后生动物中富含精氨酸-丝氨酸（RS）的结构域。这些区域中RS重复序列的密度与分支位点信号的保守性相关，为SR蛋白的祖先起源提供了证据，并表明SR蛋白和分支位点共同进化。
