关键词: 草菇；低温自溶；低温胁迫；蛋白质组学

Abstract: In order to explore the mechanism of the response of straw mushroom (Volvariella volvacea) to cold stress, the fruit body of straw mushroom was analyzed for differentially expressed proteins after cold stress treatment using isobaric tag for relative and absolute quantitation (iTRAQ) proteomic technology. A total of 2 455 proteins were quantitated including 332 differentially expressed proteins, 64 of which were up-regulated while the remaining 268 were down-regulated. Gene ontology analysis indicated that the differentially expressed proteins were involved in cellular and metabolic processes, and related to molecular functions such as binding and catalytic activity. Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis showed that the differentially expressed proteins were associated with 57 specific KEGG pathways. Using clusters of orthologous groups of proteins (COG) analysis, 328 differentially expressed proteins were annotated and classified into 22 COG functions. Moreover, the metabolic processes in which the differentially expressed proteins were involved in response to cold stress were very complicated, which were associated with energy metabolism, hydrolase activity, trehalose metabolism, amino acid metabolism, aminopeptidase activity, mitogen-activated protein kinase signaling pathway, active oxygen metabolism, membrane lipids metabolism, and so on. Quantitative polymerase chain reaction (qPCR) was used to validate the differential expression of glyceraldehyde-3-phosphate dehydrogenase and NADH-quinone oxidoreductase genes. The transcription levels of these genes were consistent with their protein expression levels. These results provide a theoretical basis for further investigating the response mechanism of the straw mushrooms to cold stress.

Key words: straw mushrooms; cryogenic autolysis; cold stress; proteomics