异源表达WZY2-1基因提高拟南芥植株抗旱性

脱水素是受细胞失水相关环境诱导表达的一类蛋白家族。所有的脱水素都含有保守的K片段,这段保守序列可以形成两亲性的α-螺旋,这种结构在脱水素发挥功能中起主要作用。小麦WZY2-1基因含有9个K片段,属于K9型的脱水素,能够被低温、干旱和盐胁迫诱导表达。在本实验中,纯化了WZY2-1蛋白,通过体外LDH酶保护实验发现,WZY2-1蛋白具有保护LDH酶活性的功能。通过亚细胞定位分析发现,WZY2-1蛋白主要定位于细胞核和细胞膜。为了进一步说明WZY2-1基因的功能,获得了转WZY2-1基因的拟南芥植株,通过干旱胁迫条件下转基因植株的生理指标和表型分析,发现转WZY2-1基因的拟南芥植株具有较强的抗旱能力。因此,推测小麦WZY2-1基因在植物干旱胁迫条件下具有重要功能。

Heterologous expression of WZY2-1 affects drought resistance of Arabidopsis plants

Dehydrins (DHNs) belong to a protein family whose expression may be induced or enhanced by environmental stresses that lead to cell dehydration. All DHNs contain at least one motif, or K-fragment, which can form an amphipathic helix. This structure play an important role in DHN function. The wheat gene WZY2-1, a K9-type DHN gene, can be activated by low temperature, drought and salt stress. In this work, the WZY2-1 recombinant protein was purified. In vitro lactate dehydrogenase (LDH) assays revealed that WZY2-1 had a potent protective effect during freezing-thawing temperature stresses. Subcellular localization showed that WZY2-1 was localized in the nucleus and cell membrane. To further elucidate the function of WZY2-1 in plants, transgenic Arabidopsis plants that overexpress WZY2-1 were tested. The transgenic Arabidopsis lines showed a better tolerance to drought stress than unmodified. This suggests that the WZY2-1 gene may also play an important role in drought tolerance in wheat.