小黑杨环锌指蛋白基因功能分析

Function Analysis of a Ring Zinc-Finger Gene in Populus simonii × P.nigra

应用RACE技术克隆出具有完整开放读码框的小黑杨环锌指蛋白基因(PsnRZF),该基因全长1061bp,其中5’非翻译区为184bp,3’非翻译区为82bp,开放读码框为795bp,编码264个氨基酸。实时定量PCR检测的结果显示,正常生长条件下该基因在根茎叶中都表达,NaCl胁迫下,该基因在根茎叶中的表达量升高。在叶中的表达量随着处理时间的延长而逐渐升高,胁迫处理后第6天表达量达到最高。为验证小黑杨环锌指蛋白(PsnRZF)基因的功能,构建植物表达载体,利用农杆菌介导法将小黑杨环锌指蛋白基因导入烟草中。通过对正常生长条件下和盐胁迫条件下,转基因烟草生理指标的检测发现:在正常生长条件下,PsnRZF基因的过量表达导致植物膜脂氧化程度增强;但在盐胁迫条件下,PsnRZF基因的过量表达可以缓解膜脂的过氧化作用。

The 1061 bp full length cDNA of ring zinc - finger gene was isolated by rapid amplification of eDNA ends （RACE） ,including a 184 bp 5＇untranslated region,an 82 bp 3＇untranslated region antta 795 bp open reading frame encoding 264 amino acid residues. Real - time PCR revealed that PsnRZF gene was expressed in roots,stems and leaves under normal growth, and the expression level was increased under salt - stress. The expression level of PsnRZF gene in leaves was increased gradually antt the peak value was appeared at the 6th day under NaC1 stress. To verify PsnRZF gene function,the plant expression vector with PsnRZF gene was constructed,and transformed tobacco was performed by agrobacterium -mediated method. Physiological analysis showed that over expression of PsnRZF gene is harmful to plant under normal condition. But over expression of PsnRZF gene under salt stress can relieve the damage of membrane lipid oxidation.