Gao Mengjie, Mei Xinglin, Li Cong, Yu Pengcheng, Shen Dongxu, Zhao Qiaoling
School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China.
The Sericulture Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, Jiangsu, China.
Arch Insect Biochem Physiol. 2021 May;107(1):e21774. doi: 10.1002/arch.21774. Epub 2021 Mar 10.
The expression levels of some intrinsic genes, protease activity, and regulation of signaling pathways were distinct during different growth and development stages in the silkworm, Bombyx mori. The silkworm mutant mini was discovered from the normal silkworm strain S8V, and the body-size of the mini mutant was smaller than the wild-type from the second-instar and the difference became more significant in the following stages. In this study, genetic analysis of mini mutant showed that mini mutant was controlled by a single recessive gene, manifested as homozygous lethal. Then, the transcriptome analysis of the mini mutant indicated that 2944 differentially expressed genes (DEGs) were identified from the silkworm in the 48 h of the second-instar, of which 1638 genes in the mini mutants were upregulated and 1306 genes were downregulated. These DEGs were mainly distributed in the biological process, cellular component, and molecular function. The functional annotation based on the KEGG database showed that these genes were mainly clustered in metabolic pathways, fatty acid metabolism pathways, ribosome biogenesis in eukaryotes, and so on. Further analysis indicated that some genes involved in the growth and metabolism including enzyme genes, juvenile hormone, and ecdysone exhibited different transcriptional levels. These results provided new experimental evidence regarding the mechanism of the underlying formation of mini mutants.
在家蚕不同的生长发育阶段，一些内在基因的表达水平、蛋白酶活性以及信号通路的调控存在差异。家蚕突变体mini是从正常家蚕品系S8V中发现的，从二龄期开始，mini突变体的体型就比野生型小，且在后续阶段差异更加显著。在本研究中，对mini突变体的遗传分析表明，mini突变体由单个隐性基因控制，表现为纯合致死。随后，对mini突变体的转录组分析表明，在二龄期48小时的家蚕中鉴定出2944个差异表达基因（DEGs），其中mini突变体中有1638个基因上调，1306个基因下调。这些DEGs主要分布在生物过程、细胞成分和分子功能中。基于KEGG数据库的功能注释表明，这些基因主要聚集在代谢途径、脂肪酸代谢途径、真核生物核糖体生物发生等方面。进一步分析表明，一些参与生长和代谢的基因，包括酶基因、保幼激素和蜕皮激素，表现出不同的转录水平。这些结果为mini突变体潜在形成机制提供了新的实验证据。
