Proteomic changes associated with the initiation and termination of aestivation in the cabbage stem flea beetle

Abstract

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=79 SRC="FIGDIR/small/655265v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@18535d2org.highwire.dtl.DTLVardef@908d8borg.highwire.dtl.DTLVardef@3cdc76org.highwire.dtl.DTLVardef@1ade6e6_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIAestivation initiation is associated with a reduction in translation proteins C_LIO_LIAestivation termination involves changes in proteolysis-related proteins C_LIO_LI23-30% of the changes at the protein level were coherent with the RNA-seq study C_LIO_LITAG and chitin peak, while ATP and glucose get depleted during aestivation C_LI The cabbage stem flea beetle (CSFB, Psylliodes chrysocephala) is a major pest of oilseed rape crops and exhibits obligatory adult aestivation, summer diapause, that coincides with the summer season. The aestivation in CSFB is characterized by metabolic suppression, cessation of feeding, and reproductive activities. Previous investigations have employed RNA-seq to explore gene expression changes associated with aestivation, providing initial insights into the molecular pathways. However, studies assessing proteomic changes during aestivation in this species and insects more broadly have been lacking. In this study, we conducted a comprehensive quantitative proteomic analysis of adult CSFB at four time points: pre-aestivation (day 5), aestivation initiation (day 15), aestivation maintenance (day 30), and post-aestivation (day 55), to investigate proteomic changes associated with aestivation. We found that proteins related to the central dogma decreased in abundance, and metabolism-related proteins were altered during the initiation of aestivation. The proteomic changes during aestivation were minor and included reduction in mitochondrial proteins. Notably, the proteolysis-related proteins were enriched at the termination of aestivation. Interestingly, we observed discrepancies between our previous RNA-seq results and the proteomic data, particularly in the genes that increased in abundance during aestivation compared to post-aestivation. This highlights the importance of proteomic analysis for a more complete understanding of molecular mechanisms underlying aestivation. Body composition measurements showed that triglyceride and chitin levels peaked, while ATP and glucose were depleted during aestivation, following the changes in proteins belonging to different biological pathways.