EXPRESSION ANALYSIS AND CHROMOSOMAL ASSIGNMENT OF THE HUMAN SFRS5 SRP40 GENE/

Alternative splicing plays a major role in the regulation of gene expr ession, SFRS5/SRp40 is a member of the serine/arsnine (SR) protein fam ily of regulators of alternative pre-mRNA splicing, We cloned the huma n SFRS5 cDNA and observed two major SFRS5 transcripts, an similar to 1 .8-kb short form and an similar to 3.3-kb long form, in both human and rat tissues. Both transcripts were detected in all human tissues exam ined, but there were notable tissue-specific differences in their rela tive abundance, the short form being most abundant in retina. Affinity -purided SFRS5 antisera recognized a single 40-kDa polypeptide in huma n and mouse retinal lysates. The abundant retinal expression of SFRS5 was not restricted to any specific cell type, since immunofluorescent labeling of human retinal sections identified the SFRS5 protein in nuc lei of all three nuclear layers of the retina. The human SFRS5 gene wa s localized to human chromosome 14q24 by fluorescence in situ hybridiz ation and PCR analysis of a human/hamster somatic cell hybrid panel. ( C) 1997 Academic Press.