{"title":"Mechanism of starvation induced autophagy and apoptosis in the midgut of silkworm, Bombyx mori, based on calcium homeostasis.","authors":"Jialu Cheng, Xueling Qin, Bing Han, Haoyi Gu, Hongbing Zou, Peiling Peng, Zhongxu Mao, Bing Li","doi":"10.1111/imb.12981","DOIUrl":null,"url":null,"abstract":"<p><p>Starvation can induce autophagy and apoptosis in intestinal cells. To elucidate the underlying mechanisms, we investigated autophagy and apoptosis in the midgut of the model insect, silkworm (Bombyx mori), focusing on calcium homeostasis. The results indicated that the body weight of silkworms decreased, along with damage to the morphology of their digestive tracts and midguts after starvation treatment. Additionally, mitochondrial swelling, autophagy and apoptosis were observable. Further investigation revealed that starvation upregulated the transcription of Ca<sup>2+</sup> release channel-associated genes (e.g., BmIP3R, BmRyR) but suppressed the expression of Ca<sup>2+</sup> efflux genes (BmPMCA), resulting in Ca<sup>2+</sup> overload in midgut cells and subsequent upregulation of BmCalpain transcription. In addition, starvation increased the transcription of key autophagy genes (BmATG5, BmATG7, BmATG8) and the expression of the LC3-II protein. Upon prolonged starvation, the NtATG5 protein levels increased, a process that facilitated the transition from autophagy to apoptosis. These results indicate that Ca<sup>2+</sup> overload activates the calpain-mediated apoptosis pathway and promotes apoptosis of midgut cells. The present study reveals the significant role that Ca<sup>2+</sup> plays in the occurrence and transformation of autophagy and apoptosis induced by starvation treatment, thus providing a new research strategy for investigating the damage caused by starvation in biological organisms.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":" ","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Insect Molecular Biology","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1111/imb.12981","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Starvation can induce autophagy and apoptosis in intestinal cells. To elucidate the underlying mechanisms, we investigated autophagy and apoptosis in the midgut of the model insect, silkworm (Bombyx mori), focusing on calcium homeostasis. The results indicated that the body weight of silkworms decreased, along with damage to the morphology of their digestive tracts and midguts after starvation treatment. Additionally, mitochondrial swelling, autophagy and apoptosis were observable. Further investigation revealed that starvation upregulated the transcription of Ca2+ release channel-associated genes (e.g., BmIP3R, BmRyR) but suppressed the expression of Ca2+ efflux genes (BmPMCA), resulting in Ca2+ overload in midgut cells and subsequent upregulation of BmCalpain transcription. In addition, starvation increased the transcription of key autophagy genes (BmATG5, BmATG7, BmATG8) and the expression of the LC3-II protein. Upon prolonged starvation, the NtATG5 protein levels increased, a process that facilitated the transition from autophagy to apoptosis. These results indicate that Ca2+ overload activates the calpain-mediated apoptosis pathway and promotes apoptosis of midgut cells. The present study reveals the significant role that Ca2+ plays in the occurrence and transformation of autophagy and apoptosis induced by starvation treatment, thus providing a new research strategy for investigating the damage caused by starvation in biological organisms.
期刊介绍:
Insect Molecular Biology has been dedicated to providing researchers with the opportunity to publish high quality original research on topics broadly related to insect molecular biology since 1992. IMB is particularly interested in publishing research in insect genomics/genes and proteomics/proteins.
This includes research related to:
• insect gene structure
• control of gene expression
• localisation and function/activity of proteins
• interactions of proteins and ligands/substrates
• effect of mutations on gene/protein function
• evolution of insect genes/genomes, especially where principles relevant to insects in general are established
• molecular population genetics where data are used to identify genes (or regions of genomes) involved in specific adaptations
• gene mapping using molecular tools
• molecular interactions of insects with microorganisms including Wolbachia, symbionts and viruses or other pathogens transmitted by insects
Papers can include large data sets e.g.from micro-array or proteomic experiments or analyses of genome sequences done in silico (subject to the data being placed in the context of hypothesis testing).