Evolutionary And Transcriptional Exploration Of Karyopherin β Superfamily Proteins

Karyopherinβsuperfamily is a group of proteins which widely spread in eukaryotic cells.They play a key role in mediating nucleocytoplasmic transport of macromolecules.Because of their diversity in sequence compositions and structure, they bind varied cargos and function in different ways.Currently karyopherinβsuperfamily is not well studied worldwide,and it's still unclear about the origin and function evolvement of this family.In this study,we investigated the evolutionary and transcriptional patterns of these proteins in 8 genomes(Saccharomyces Cerevisiae, Caenorhabditis elegans,Drosophila melanogaster,Danio rerio,Xenopus tropicalis, Gallus gallus,and Mus musculus and Homo sapiens) with the help of phylogenetic analysis,microarray expression profile analysis and prediction of transcription factor binding sites.Among 14β-karyopherins in Saccharomyces cerevisiae,8 corresponded to their human orthologs directly without diversification(KAP95,KAP114,KAP120, KAP123,CSE1,MSN5,CRM1 and LOS1),2 were lost(KAP122 and SXM1),and the remaining 4 proteins(PSE1,NMD5,MTR10 and KAP104) exhibited gene duplications by different mechanisms.β-Karyopherins were ubiquitously but nonuniformly expressed in distinct cells and tissues.In yeast and mice,the titer of someβ-karyopherin transcripts appeared to be regulated both during the cell cycle and during development.Further virtual analysis of promoter binding elements suggested that transcription factors SP1,NRF-2,HEN-1,RREB-1 and NF-Y regulate expression of mostβ-karyopherin genes.These findings illuminated close relationship between functional evolution ofβ-karyopherins and their diversity in gene expression and regulation patterns.