家蚕化学感受蛋白BmCSPs基因在高温应答中的功能解析

Hot and humid climate of Southern China sericultural area has made great demand for strong stress resistant silkworm varieties from sericultural production. New breeding technology which can improve stress resistance of varieties significantly based on maintaining the economic character has become a bottleneck of sericulture industry upgrading and developing. This project is to carry out basic research related to the prominent problem which sericultural production in Southern China is facing. Previous research results of our group by high-throughput analysis showed that some of Bombyx mori chemosensory protein BmCSPs genes existed significant differences in expression in midgut before and after high temperature stimulation. In the project, we intends to analyse time and tissue expression profile of all the BmCSPs members after high temperature induction, screen of differentially expressed BmCSPs, clone promoter sequence of BmCSPs in silkworm varieties with different resistance to high temperature, carry out correlation analysis between resistance difference to high temperature and gene sequence differences, study key BmCSPs function in response to high temperature of silkworm through overexpression and genome editing technology, combined with biological characters analysis including high temperature tolerance, expression level of genes related to high temperature and antioxidant enzyme activity. The results of this research will provide reference for breeding high temperature resistant silkworm varieties through transgenic technology, and has important theoretical and practical significance to push forward steady development of sericulture industry.

华南蚕区高温多湿的气候环境使抗逆性蚕品种在蚕业生产中有着极大的需求，在保持经济性状的基础上显著提高品种抗逆性水平的育种新技术已经成为制约蚕桑产业升级发展的一大瓶颈，本项目正是基于蚕业生产面临的这一突出问题而开展相关基础研究。课题组前期通过高通量分析发现家蚕化学感受蛋白BmCSPs基因部分成员在高温刺激前后的蚕体内存在显著差异性表达。本项目拟对全部BmCSPs成员在高温诱导后的时间和组织表达模式进行分析，筛选发生差异表达的BmCSPs基因，克隆不同高温耐受力的蚕品种BmCSPs基因的启动子序列，分析高温耐受力与基因序列差异之间的相关性，并通过基因过表达和基因组编辑技术，结合高温耐受力、耐高温相关基因表达和抗氧化酶活力检测等生物学性状分析，解析关键BmCSPs基因在家蚕高温应答中的功能，为进一步利用转基因技术选育耐高温优良蚕品种提供参考，对推动蚕桑产业的稳定发展具有重要的理论和实践意义。

华南地区地处高温多湿的气候环境，对抗逆性蚕品种在蚕业生产中有着极大的需求。长期以来华南家蚕品种选育均采用传统育种技术，将抗逆性状导入实用性品种。由于抗逆性状与产量质量性状之间存在相互制约的关系，因此亟需利用分子育种突破两者间的瓶颈制约，在保持蚕茧产量质量的前提下显著提高品种的抗逆性水平。在前期研究中我们通过DGEP测序分析获得了与家蚕高温耐受能力相关基因，本项目对其中的家蚕化学感受蛋白BmCSPs基因进行了高温应答中的功能解析。通过实时荧光定量PCR探明了家蚕化学感受蛋白BmCSPs在5龄家蚕中受高温胁迫的时间表达模式和空间表达模式，筛选出发生显著差异表达的BmCSP7、BmCSP11、BmCSP15等基因。比较分析了耐高温品种932G和敏感性品种HY的BmCSP7、BmCSP11基因序列差异，测序结果表明BmCSP7基因序列在两个品种间无差异，而BmCSP11则存在31个突变位点，推测可能与品种的耐受性密切相关。初步解析了BmCSP7、BmCSP11和BmCSP15等关键BmCSPs基因在高温应答中的功能，过表达实验结果表明BmCSP11和BmCSP15在细胞受高温胁迫早期发挥一定的作用，维持细胞正常增殖，BmCSP7则对细胞的高温耐受具有抑制作用。转录组与代谢组联合分析结果表明，高温胁迫前后的差异基因与代谢物主要富集于氨基酸代谢、细胞自噬等途径，进一步揭示了家蚕高温应答机制。发表学术论文3篇，其中SCI论文1篇。申请发明专利1项，取得软件著作权1件，培养研究生1名。本研究获得高温应答关键BmCSPs基因并对其在家蚕高温应答中的功能进行解析，为揭示家蚕耐高温分子机制提供了科学依据，此外具有促高温耐受性功能的BmCSP11基因可为耐高温分子育种提供参考，对推动蚕桑产业的稳定发展具有重要的理论和实践意义。