在茶树(Camellia sinensis)的生长发育过程中,干旱、盐害等非生物胁迫频繁发生,对茶叶的产量和品质造成了显著不利影响。聚焦于茶树磷脂:二酰甘油酰基转移酶1基因(CsPDAT1),通过生物信息学分析、基因表达模式检测以及转基因功能验证等手段,系统探究了该基因在非生物胁迫响应中的功能。生物信息学分析表明,CsPDAT1编码的蛋白具有典型的溶血磷脂酰基转移酶(lysoPLA)结构域。实时荧光定量PCR结果显示,CsPDAT1在干旱及高盐处理下表达量显著上调,尤其在干旱胁迫初期表现明显。为深入解析其功能,构建了CsPDAT1过表达载体并转化拟南芥,成功获得3个纯合的T3代转基因株系。表型分析发现,在干旱胁迫下,过表达CsPDAT1的拟南芥植株种子萌发率显著高于野生型,丙二醛(MDA)含量降低,脯氨酸含量增加,且抗氧化酶活性显著增强。本研究证实CsPDAT1通过调控细胞膜脂代谢和渗透调节物质积累,增强植株对非生物胁迫的耐受性,为茶树抗逆分子育种提供了理论基础和基因资源。
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