关键词: 杆状病毒, 核型多角体病毒, 颗粒体病毒, 蜕皮甾体尿苷二磷酸葡萄糖基转移酶, 尿苷二磷酸葡萄糖醛酸转移酶, 进化起源

Abstract: The fragment of ecdysone UDP-glucosyltransferase gene (egt）was obtained by PCR from Bombyx mori nuclearpolyhedrosis virus (BmNPV), and sequence analysis showed that it contained the complete ORF of EGT which could form advanced structure of EGT functional region. Furthermore, for exploring the origin of egt, several putative uridine diphosphate glucosyl/glucuronosyltransferase genes (UGTs) of B. mori were electronically cloned. Evolutionary analysis indicated that EGT of BmNPV was of antennal-enriched UGT. Moreover, egt genes from nucleopolyhedrivirus (NPV) and granulovirus (GV) were presumed to originate from insect UGT gene, but the evolutionary origin of GV egt was earlier than that of NPV. During the stage of ancestor species evolving to different insects, the ancestor species of baculovirus might have obtained antennal-enriched UGT, which evolved to egt gene later. In the silkworm genome, part of UGT gene is closely linked with transposon, indicating that baculovirus had obtained egt gene through transfer of the transposon.

Key words: Baculovirus, nucleopolyhedrivirus (NPV), granulovirus (GV), ecdysone UDP-glucosyl-transferase, uridine diphosphate glucosyl/glucuronosyltransferase（UGT）, evolutionary origin