中文摘要：

【目的】Sox家族是一类转录调控因子,在多细胞动物的发育过程中起到了极其重要的作用。本研究旨在获得家蚕Bombyx mori Sox家族基因,并分析其在幼虫不同组织和发育阶段的表达模式及功能。【方法】采用cDNA末端快速扩增方法（rapid amplification of cDNA ends,RACE）克隆家蚕Sox家族基因,并对其序列进行生物信息学分析。构建原核表达载体,诱导原核表达并得到其蛋白的多克隆抗体,并以Western blot验证其蛋白在家蚕胚胎发育时期（产卵后24,48,72,96,120,144,168,192和216 h）和蚁蚕的表达特征。同时,使用半定量RT-PCR技术分析这一基因在家蚕整个发育过程以及5龄第3天幼虫不同组织（精巢、卵巢、神经节、头部、丝腺、脂肪体、马氏管、中肠、后肠、表皮、血液、气管）中的表达谱。【结果】克隆获得一个家蚕Sox家族基因,将其命名为BmDichaete（Gen Bank登录号：KY914554）,其cDNA序列全长为1 541 bp,开放阅读框长741 bp,编码246个氨基酸,预测分子量大小为27.3 kD,等电点为9.89。同源序列比对和系统进化分析显示,BmDichaete具有Sox家族的典型HMG结构域,并与其他鳞翅目昆虫的Dichaete蛋白具有较高的同源性。对其表达模式分析发现,BmDichaete在家蚕整个发育时期都有表达,从胚胎发育后期到蛹前期持续高表达,在蛹后期及成虫期表达量有所下降,并且该基因在家蚕5龄第3天幼虫的卵巢、头部、丝腺及后肠组织中显著高表达。Western blot分析结果显示,BmDichaete在家蚕胚胎发育过程中持续而稳定地表达。【结论】家蚕BmDichaete具有典型HMG结构域,属于Sox家族成员。BmDichaete在家蚕胚胎发育的各个时期都发挥作用。本研究为进一步探索该基因在家蚕中的功能奠定了基础。

英文摘要：

【Aim】The Sox family is a group of transcription factors and plays essential roles during the development of multicellular animals.This study aims to clone a Sox family gene from the silkworm,Bombyx mori,and to explore its expression pattern and function in different larval tissues and developmental stages of the silkworm.【Methods】A gene of the Sox family was cloned from the silkworm using rapid amplification of cDNA ends（RACE） and its sequence was analyzed with bioinformatics tool.The prokaryotic expression vector was constructed to induce the expression of protein and produce its antibody to test the expression characteristics of the protein during the embryonic development（24,48,72,96,120,144,168,192 and 216 h after oviposition） and newly hatched larvae of the silkworm by Western blot.Meanwhile,semi-quantitative RT-PCR was used to identify the gene expression profiles during the entire developmental period and in different tissues（testis,ovary,ganglion,head,silk gland,fat body,Malpighian tubules,midgut,hindgut,cuticle,blood,trachea） of the 5th instar day-3larvae.【Results 】 A Sox family gene named BmDichaete（Gen Bank accession no.：KY914554） was cloned from B.mori,and its full-length cDNA sequence is 1 541 bp and the open reading frame is 741 bp,encoding a protein of 246 a.a.with an estimated molecular mass of 27.3 kD and pI of 9.89.The results of the homologous sequence alignment and phylogenetic analysis showed that BmDichaete has the typical HMG domain of the Sox family gene,and high homology with the Dichaete proteins of other lepidopteran insects.The expression profiling showed that BmDichaete possessed higher expression levels from the late stage of embryonic development to the early stage of pupation,while its expression level decreased in the late stage of pupation and adult stage.Moreover,BmDichaete was significantly overexpressed in the ovary,head,silk gland and hindgut.The expression characteristic analysis by Western blot indicated that BmDichaete was expressed continuous