Expression Characteristic of TaPDC-E1α Gene and Its regulatory Enzymes Gene in Male Sterile Line of 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.

摘 要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-E1α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-E1α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-E1α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。