中文摘要：

家蚕质型多角体病毒（Bombyx mori cytoplasmic polyhedrosis virus,BmCPV）是家蚕的重要病毒病原之一,往往给养蚕业生产造成极大危害。我们以前的研究运用基因芯片技术在感染质型多角体病毒的家蚕中肠中鉴定出一个差异表达的3-羟酰辅酶A脱氢酶蛋白基因（Bombyx mori3-hydroxyacyl-CoA dehyrogenase protein gene-Bm3HAD）。本研究利用cDNA末端快速扩增技术（RACE）克隆了该基因,其全长cDNA序列为1168bp,包含一个83bp5＇端非翻译区序列（5＇-UTR）、一个930bp的开放阅读框（ORF）和一个155bp的3＇端非翻译区序列（3＇-UTR）;基因结构分析发现该基因由5个外显子和4个内含子组成。RT-PCR结果显示该基因在家蚕中肠、脂肪体、血液、丝腺及生殖体中均有表达。荧光定量PCR结果表明该基因在BmCPV感染初期为上调表达,随着病毒感染的进展,该基因的表达水平逐渐降低,并转变为下调表达。研究结果为进一步研究BmCPV对家蚕致病的分子机制提供了有益的信息。

英文摘要：

Silkworm（Bombyx mori） cytoplasmic polyhedrosis virus（BmCPV） is a main viral pathogen for silkworm and always causes severe damage to commercial sericultural production.In our previous study,a differentially expressed gene,Bm3HAD,was identified in the midgut of silkworm larvae infected with BmCPV by using microarray analysis.In this study,the full-length cDNA of Bm3HAD gene was cloned and analyzed with rapid amplification of complementary DNA ends（RACE）.This gene is 1 168 bp and has a 83 bp 5＇-untranslated region（5＇-UTR）,a 930 bp open reading frame（ORF） and a 155 bp 3＇-UTR.Gene structure analysis indicates that this gene has five exons and four introns.RT-PCR analysis revealed that Bm3HAD was expressed in all the tissues tested,including midgut,hemocyte,fat body,silk gland and gonad.Real-time quantitative PCR detection revealed that relative expression of Bm3HAD in the midgut of infected silkworm was up-regulated in the early stage of infection,but gradually decreased as the infection progressed and then became down-regulated.The results are informative for exploring the molecular mechanism involved in the infection of silkworm with BmCPV.