Label-free quantitative proteomic analysis of insect larval and metamorphic molts

Abstract

Background Molting is an essential biological process occurring characteristic times throughout the life cycle of holometabolous insects. However, it is not clear how insects determine the direction of molting to remain status quo or to initiate metamorphosis. To explore the functional factors that determine the direction of molts, liquid chromatography-mass spectrometry was used to identify the molecules involved in larval and metamorphic molting, and the differentially expressed proteins (DEPs) were compared in the two processes. Results There were 321 and 1140 DEPs identified in larval and metamorphic molting process, respectively. Bioinformatics analyses show that the amino sugar pathway was up-regulated in both processes. The up-regulated protease contributed to the metamorphosis. In addition, several proteins with different expression patterns in larval-larval and larval-pupal transitions, including Endochitinase, GRIM-19 (Genes associated with retinoid-IFN-induced mortality-19), IDE (Insulin-degrading enzyme), Sorcin (Soluble resistance related calcium binding protein), OBP (Odorant-binding protein-2 precursor), TRAP1(Tumor necrosis factor receptor associated protein-1), etc., were further identified by parallel reaction monitoring, which may play diverse functions in larval-larval and larval-pupal transitions. Conclusions These results provide a proteomic insight into molecules involved in larval and metamorphic molts, and will likely improve the current understanding of determination of direction of molts.

Whole-transcriptome profiling across different developmental stages of Aedes albopictus (Diptera: Culicidae) provides insights into chitin-related non-coding RNA and competing endogenous RNA networks

“…Similar results were also found in the molting of Helicoverpa armigera at the proteomic level. Upregulated proteins in larval and metamorphic molting of H. armigera were found to be enriched in the amino sugar metabolism pathway, lipid transport process, and protein catabolism, which are related to the metabolism of chitin [ 60 ].…”

Alternative splicing of chitin deacetylase 2 regulates chitin and fatty acid metabolism in Asian citrus psyllid, Diaphorina citri

“…Molting is an important biological process occurring at characteristic times throughout the life cycle of insects (Si et al, 2020). Insects must shed old cuticles and synthesize new cuticles periodically to allow growth and metamorphosis (Song, 2012).…”