iTRAQ-based proteomic analysis of fertile and sterile flower buds from a genetic male sterile line 'AB01' in Chinese cabbage (Brassica campestris L. ssp. pekinensis)

摘要

To investigate the molecular basis of multiple-allele-inherited male sterility in Chinese cabbage (Brassica campestris L. ssp. pekinensis), we performed differential proteomic analysis using iTRAQ to identify differentially abundant proteins between fertile and sterile flower buds from the genetic male sterile line 'AB01'. We identified 5932 high-confidence proteins; 1494 were differentially abundant between the two samples, including 749 up-and 745 down-regulated proteins. The up- and down-regulated proteins that could be essential for anther development and male sterility in sterile buds were mainly involved in (1) carbohydrate and energy metabolism (pyruvate dehydrogenase, glycolysis/gluconeogenesis, TCA cycle, starch and sucrose metabolism), (2) pollen wall synthesis and regulation (pectinesterase, polygalacturonase, pectate lyase, beta-galactosidase, glycosyl hydrolase), (3) protein synthesis and degradation (proteasome subunits, ribosome proteins, ABC transporters, RNA transport, protein processing in endoplasmic reticulum), (4) flavonoid biosynthesis, and (5) plant hormone signal transduction. We identified 10 genes/proteins that were both up-regulated and 122 that were both down-regulated in a conjoint analysis. Multiple reaction monitoring and qRT-PCR validation showed that the iTRAQ results were accurate and reliable. These findings will provide valuable information on proteins involved in anther development, and will contribute to the understanding of the molecular mechanism(s) that underlie male sterility in Chinese cabbage.