过表达围食膜因子基因Bm09641家蚕中肠转录组分析

Transcriptomic Analysis of Midgut from Silkworm Overexpressing Peritrophin Gene Bm09641

昆虫围食膜因子是一类重要的蛋白,其保守的几丁质结合结构域介导它与几丁质的结合,对维持围食膜的物理性质、通透性结构及抗性功能至关重要。家蚕围食膜因子在幼虫中肠特异表达。为解析围食膜因子对外源病原体的抗性机制,对过表达围食膜因子Bm09641转基因家蚕Bm09641OE 5龄第3天幼虫的中肠进行转录组测序和分析,结果发现,与对照家蚕相比,Bm09641OE中有1 263个基因表达上调,1 568个基因表达下调,分析差异表达基因发现Bm09641OE家蚕中肠的跨膜运输、跨膜转运、抗菌肽等体液免疫和细胞凋亡相关基因表达显著上调,而与三羧酸循环有关的酶基因表达显著下调。显示围食膜因子基因Bm09641可能引起幼虫的体液免疫被激活,调控中肠细胞凋亡,从而影响中肠对外源病原的抵抗功能。

Insect peritrophin is an important class of proteins whose conserved chitin-binding domain mediates its binding to chitin,which is crucial for maintaining the physical properties,permeability structure and resistance function of the peritrophic membrane.The peritrophin of silkworm is specifically expressed in the midgut of larvae.To analyze the resistance mechanism of peritrophin to exogenous pathogens,the transcriptome sequencing and analysis were carried out to the midguts of silkworm Bm09641OE whose peritrophin Bm09641 were overexpressed in the 3rd day fifth instar larvae.The results showed that compared with the control group,there were 1263 genes up-regulated and 1568 genes down-regulated in Bm09641OE.The analysis of differentially expressed genes revealed that the expression of genes related to humoral immunity and apoptosis such as transmembrane transport and antibacterial peptide were significantly upregulated,but the expression of enzymes genes related to the TCA cycle was significantly downregulated.It is shown that the peritrophin gene Bm09641 may cause the activation of humoral immunity in larvae to regulate cell apoptosis in the midgut,thus affecting the resistance function of the midgut to exogenous pathogens.