Analysis Of Proteomics In Anther Development Of Recessive Genic Male Sterile S45AB Line In Brassica Napus L.

S45AB, a near-isogenic line of a recessive genic male sterility (RGMS) system in B. napus, was derived from male sterile mutant of canola variety Oro in Sichuan University (Pan et al.,1988). Previous work has showed the BnCYP704B1, encoding a long-chain fatty acid ω-hydroxylase, was the restorer gene of the S45A mutant, the loss of BnCYP704B1function caused abnormal lipid metabolism and blocked the PCD in the tapetum of the S45A mutant, resulting in complete male sterility(Yi and Zeng et al.,2010). To make a deep investigation into the sterility mechanism of S45AB system, two-dimensional gel electrophoresis (2-DE) was used to find differentially expressed proteins in the period of abortion.Using trichloroacetic acid/acetone extraction and2-DE method, we detected744spots on2-D gels of S45A mutant and S45B anthers and of the52spots with2-fold or higher expression, all of the52spots were analyzed by MALDI-TOF mass spectrometry and49proteins were successfully identified searching against NCBI and Brassica EST databases, including28up-regulated proteins in S45B and21up-regulated proteins in S45A. Based on the results of mass spectrometry,49differently expressioned proteins can be classed into12functional categories:carbohydrate and energy metabolism, amino acid metabolism, secondary metabolism, fatty acid metabolism, RNA binding protein, protein synthesis, protein degradation, protein folding, redox enzyme cell organization, stress response proteins and unknown protein. Most of the carbohydrate and energy metabolism associated proteins were up-regulated in S45B, which indicated a strong vigor of the S45B flower buds; however, the amino acid metabolism and protein synthesis associated proteins were down-regulated in S45B, which indicated that the male sterility of S45A is associated with protein processing. Real-time PCR demonstrated that the transcript levels and protein expression levels were in coincident with selected proteins. Our work is the first proteome analysis of the sterility mechanisms in the B. napus RGMS. The results may help to shed light on the function of the restorer gene BnCYP704B1.