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为进一步研究杀雄剂SQ-1诱导小麦雄性不育的机制，采用电子克隆的方法分离 TaPDC-E1a 基因，并利用半定量RT-PCR技术分析该基因及其调节酶基因 PDK 和 PDP 的表达特性。结果表明， TaPDC-E1a 基因编码388个氨基酸，具有TPP保守结构域，可能存在2个丝氨酸磷酸化位点；与可育系相比， TaPDC-E1a 基因在生理型不育系和遗传型不育系中表达下调； PDK 基因在生理型不育系中表达下调，而在遗传型不育系中表达上调； PDP 基因在可育系及不育系中的表达趋势无明显变化。表明经杀雄剂SQ-1诱导形成的生理型不育系在败育过程中其能量代谢途径更容易受到影响，推测对 PDK 基因进行调节的上游信号机制在小麦生理型不育系与遗传型不育系中可能不一致。

The objective of this study was to explain the male sterile mechanism of wheat (Triticum aestivum L.) based on chloroplast proteome. A method for isolating intact chloroplast proteome from wheat floret was established. Using this method, the chloroplast proteomes were extracted from florets of the genic and physiological male sterile lines and their maintainer line, and separated in 2-dimensional electrophoresis (2-DE) gels. The cytoplasmic-nuclear sterile line, ms(S)-1376, had identical nuclear background with the maintainer line, (A)-1376, and the physiological male sterile line, ms(A)-1376, was derived from (A)-1376 after induction of chemical hybridizing agent SQ-1. The extraction method was effective to obtain high purity of intact chloroplast using discontinuous sucrose density gradient centrifugation with 3-step gradient densities of 30, 45, and 60%. The 2-DE result showed that the floret chloroplast protein profiles were different among the 3 lines at uninucleate anther stage, and 239 protein spots were visible on each gel (pH 4-7, molecular weight 14.4-66.2 kD). Six differentially expressed proteins were analyzed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) and indexed in bioinformation database. They were identified as acyl-CoA dehydrogenase domain protein, calmodulin-binding protein phosphatase, multiple catalytic peptidase, heat-shock protein 60, light receptor protein 2, and a protein of unknown function. These proteins are involved in series of physiological reactions such as metabolism of energy substances, chloroplast defendance, chloroplasts signal transduction, and plant growth. The differential expressions of these proteins among the 3 lines are likely related to the male sterility in wheat.

To understand the mechanism of male sterility induced by gametocide SQ-1 in wheat (Triticum aestivum L.), TaPDC-E1α gene was isolated using silcon cloning technique. The open reading frame of this gene is 1401 bp in length, putatively encoding 388 amino acid residues. This gene possesses the conserved TPP domains. Two potential phosphorylation sites of serine residues might be present in the TaPDC-E1α protein of wheat. According to semiquantitative reverse transcription polymerase chain reaction (RT-PCR) analysis, the expression levels of TaPDC-E1α in the physiological and genetic male sterile lines were lower than those in the fertile lines. Compared with the fertile lines, the expression of PDK was obviously down-regulated in the physiological male sterile line induced by SQ-1. However, PDK gene was highly expressed in the genetic male sterile lines. The expression levels of PDP gene were similar in the fertile and the male-sterile lines. These results suggest that the pathway of energy metabolism in the SQ-1 induced sterile line is more susceptible than that of the genetic male-sterile line. The upstream signal mechanism of mediating PDK gene may be inconsistent between the male-sterile line induced by SQ-1 and the genetic male-sterile line.