The Structural and Phylogenetic Analysis of Late Expression Factor 8( lef-8) Gene in Buzura suppressaria Nuclear Polyhedrosis Virus
Abstract
Late expression factor 8( lef-8) gene is an early expression gene,and codes the largest subunit of RNA polymerase in baculovirus. The authors sequenced the lef-8 gene of Buzura suppressaria nuclear polyhedrosis virus( Bs NPV). It had 2 634 bp coding region and encoding 877 amino acid residues. Some signal sequences were found in untranslated region( UTR) : possible promoter and transcription initiation site were found in 5'-UTR,and a putative polyadenylation signal sequence was found in 3 '-UTR. But whether they had substantial function needs further research. The protein sequence of lef-8 gene in Bs NPV was low homologous to model NPVs. But they had nearly the same signal sequence. By phylogenetic analysis of lef-8 gene in baculovirus,it was found that the nuclear polyhedrosis virus( NPV) and the granulosis virus( GV) was separated obviously to two branches,while the NPV broke into 4 branches. And evolutionary relationship in baculovirus was largely associated with its host.