家蚕中肠特异表达基因BmMSEG的进化和功能研究

Evolution and Function of BmMSEG Gene Expressed Specifically in the Midgut of Silkworm

中肠是家蚕消化管的最主要部分,对家蚕生长、发育以及免疫等具有重要影响。先前基于转录组分析发现,BmMSEG(midgut-specific expressed gene)基因在家蚕中肠特异表达,但是其功能仍然未知。本研究应用qRT-PCR进一步证明BmMSEG在家蚕中肠特异表达。通过CRISPR/Cas9敲除BmMSEG基因,发现敲除个体的中肠出现损伤,并且在5龄幼虫期死亡。最后通过同源搜索和共线性分析,发现BmMSEG的直系同源基因广泛且特异性分布于鳞翅目昆虫基因组中。本研究结果不仅为进一步研究BmMSEG基因导致中肠损伤的作用机制提供了理论基础,而且深入研究可为鳞翅目害虫防控提供新的分子靶标。

The midgut of Bombyx mori is the most important part of the alimentary canal,which has an important impact on the growth,development and immunity of the silkworm.BmMSEG(midgut-specific expressed gene)was previously found to be specifically expressed in the midgut of B.mori based on transcriptome data,but its function remained unknown.In this study,qRT-PCR was used to further prove that BmMSEG gene expressed specifically in the midgut.After BmMSEG being knocked out by CRISPR/Cas9,we found that the midgut of knocked-out individuals was damaged,and the knocked-out individuals died at the 5th instar larval stage.Further investigations through homology search and collinearity analysis found that the orthologous genes of BmMSEG were widely and specifically distributed in the genomes of Lepidoptera insects.Our results provide a theoretical basis for further research on the mechanism of BmMSEG gene-induced midgut damage.Moreover,in-depth research is expected to provide new molecular target for the control of lepidopteran pests.