Shen Yunwang, Zeng Xiaoqun, Chen Guanping, Wu Xiaofeng
College of Animal Sciences, Zhejiang University, Hangzhou, China.
Key Laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province, Hangzhou, China.
Insect Sci. 2022 Oct;29(5):1329-1345. doi: 10.1111/1744-7917.13001. Epub 2022 Feb 24.
Insect midgut plays a central role in food digestion and nutrition absorption. Larval silkworm midgut could be divided into 3 distinct regions based on their morphological colors. However, it remains rudimentary of regional gene expression and physiological function in larval silkworm midgut. Through transcriptome sequencing of 3 midgut compartments, a comprehensive analysis of gene expression atlas along the anterior-posterior axis was conducted. Posterior midgut was found transcriptionally divergent from anterior and middle midgut. Differentially expressed gene analysis revealed the regional specialization of digestive enzyme production, transmembrane transport, chitin metabolism, and hormone regulation in different midgut regions. In addition, gene subsets of pan-midgut and region-specific transcription factors (TFs) along the length of midgut were also identified. The results suggested that homeobox TFs might play an essential role in transcriptional variations across the midgut. Altogether, our study provided the first fundamental resource to investigate physiological function and regulation mechanism in larval midgut compartmentalization.
昆虫中肠在食物消化和营养吸收中起着核心作用。基于形态颜色，家蚕幼虫中肠可分为3个不同区域。然而，家蚕幼虫中肠区域基因表达和生理功能仍处于初级阶段。通过对3个中肠部分进行转录组测序，对沿前后轴的基因表达图谱进行了全面分析。发现后肠在转录上与前肠和中肠不同。差异表达基因分析揭示了不同中肠区域在消化酶产生、跨膜运输、几丁质代谢和激素调节方面的区域特化。此外，还鉴定了整个中肠的泛中肠基因子集和沿中肠长度的区域特异性转录因子（TFs）。结果表明，同源框转录因子可能在整个中肠的转录变化中起重要作用。总之，我们的研究为研究家蚕幼虫中肠分区的生理功能和调控机制提供了首个基础资源。
