共转化法获得蒙农杂种冰草转基因植株

Transgenic Wheatgrasses (Agropyron cristatum×A. desertorum cv.‘Hycrest-Mengnong’) Generated by Co-transformation

【目的】利用基因工程技术对冰草属植物进行遗传改良在国内外尚属空白,为加快冰草属植物种质改良进程,培育更为优良的冰草品种,本研究在多年冰草种质资源搜集与育种的基础上,开展冰草基因工程研究。【方法】以冰草属(Agropyron Gaertn.)中的一个优质种间杂种–“蒙农杂种”冰草(A.cristatum×A.desertorum cv.‘Hycrest-Mengnong’,)为材料,在以幼穗为外植体建立的冰草组织培养再生体系基础上,以调控脯氨酸生物合成最后一步的关键酶的突变体基因p5CS为目标基因,bar基因为筛选标记基因,进行共转化,利用基因枪轰击冰草幼穗诱导的愈伤组织。【结果】获得转基因植株;PCR和Southern检测表明外源基因p5CS已整合到冰草的基因组DNA中;RT-PCR检测表明目的基因已在冰草转基因植株的转录水平表达;p5CS基因的遗传转化率为0.11%。【结论】共转化法转化冰草方法可行,本研究结果可以为冰草的遗传改良提供新种质。

[Objective] In order to provide genetically improved new wheatgrass germplasm resources, wheatgrass genetic transformation research was studied based on years of breeding and germplasm collection work. [Method] Transgenic wheatgrasses generated from hybrid wheatgrass （,4. cristatum ×A. desertorum cv. ＇Hycrest-Mengnong＇） were examined. Based on established regeneration system, p5CS, the gene that regulates last step of proline synthesis in plants, was transformed into wheatgrass with phosphinothricin acetyltransferase （bar） conferring herbicide resistance as selecting gene. The transformation process was conducted through microprojectile bombardment of callus derived from immature inflorescence by method of co-transformation. [Result] Results of PCR and Southern analysis displayed that the exogenous p5CS gene was integrated into transgenic wheatgrass genome. RT-PCR assay showed that transgenic p5CS expressed at transcription level in transgenic plants. Transgenic frequency ofp5CS genewas 0. 11%. [ Conclusion ] The transformation was feasible through microprojectile bombardment by co-transformation. Transgenic plants obtained could provide new germplasm resource used in genetica improvement of wheatgrass.