Bio-informatic Analysis Of Evolution And Transcription Of Karyopherin β Superfamily

Karyopherinβsuperfamily proteins mediate most nucleocytoplasmic transport of macromolecules in eukaryotes. Previous study has discovered the physiological and developmental regulation mechanism of nucleocytoplasmic transport, while little is known about the evolution and expression pattern of Karyopherinβfamily. In this study we use bioinformatics approaches to investigate the uncoverd issues. By constructing the phylogenetic tree of karyopherinβfamily members in S. cerevisiae, C.elegans, D.melanogaster, D. rerio, X.tropicalis, G.gallus, M.musculu and H. sapiens, we presumed that ten karyopherin ancestors in S. cerevisiae (KAP95, KAP123, KAP114, KAP120, KAP122, CRM1, MSN5, LOS1, MTR10 and CSE1) and one ancestor of XPO6 in D.melanogaster evolve directly into their human orthologs without diversification. The other four ancestors in S.cerevisiae (KAP104,NMD5/SXM1和PSE1) and one ancestor of XPO7 in C.elegans exhibit gene duplication or intron deletion, then evolve into their paralogs in human. Further study of their gene expression patterns showed that most Karyopherins are ubiquitously but unevenly expressed in distinct tissues and organs. In mice, the titer of some karyopherins' transcripts appears to be precisely regulated during development. Further virtual analysis of promoter binding elements suggests that most karyopherin genes are regulated as housing-keeping gene, and transcription factors C/EBP, MAZ, NF-1 and Sp-1 may play the key role in initiating and regulating of most karyopherin genes' expression. These findings give us better understanding of the mechanisms in the functional and transcriptional diversification of karyopherinβfamily during eukaryote evolution.