水稻中p5cs基因的存在及其在高脯氨酸变异系中的作用

The Presence of p5cs Gene in Rice and Its Function in Pro-line-overproducing Rice Plant Lines

用来自豇豆根瘤的脯氨酸合成酶△’-吡咯啉-5-羧酸合成酶（P5CS）cDNA作探针进行杂交分析，结果表明水稻中存在豇豆根瘤P5cs基因的同源序列，它在盐胁迫条件下转录水平提高。水稻高脯氨酸变异系杂交后代株系的脯氨酸含量和耐盐性均明显高于原始型。应用水稻高脯氨酸变异系为材料进行的试验，结果显示高脯氨酸特性和高耐盐性与此基因的存在及其转录水平的提高有相关性。

Hybridization analysis wasconducted using proline synthase △ '-pyrroline - 5 - carboxylate synthetase(P5CS) cDNA from root nodule of cowpea as probe. The results indicated thepresence of the homologue sequence ofp5cs gene of cowpea nedule in rice plant(Fig. 3 ). Its transcription level increased under salt stress (Fig. 5). Theproline content and salt tolerane of thefilial generation (F9) of proline-overproducing rice plan lines were markedlyhigher than those of the original type(Figs. 1, 2). Using these proline-over-producing rice plant lines as experimental materials to conduct hybridizationanalysis, it has been shown that the highproline content charateristics and increased salt tolerance are correlated tothe presence of this gene and its increased transcription level (Figs. 3 ~ 5 ).