刚毛柽柳ThBADH基因的克隆和表达分析

Cloning and Expression Analysis on ThBADH Gene from Tamarix hispida

甜菜碱醛脱氢酶是甜菜碱合成的关键酶,能通过调节植物生理生化过程参与多种非生物胁迫响应.本研究从刚毛柽柳中克隆,获得一条BADH基因,命名为ThBADH基因.该基因有一个完整的开放阅读框架,其核苷酸序列全长为1512bp,编码了503个氨基酸.预测其蛋白质分子量为54.58kD,理论等电点PI为5.21.qRT-PCR结果显示,在激素胁迫下,如JA、GA3、ABA胁迫下,ThBADH基因能被诱导,但是表达不是很显著;而在非生物胁迫NaCl和PEG6000处理条件下,ThBADH基因能被显著诱导;与对照相比,ThBADH基因诱导表达量最高,分别为对照的90.51倍和30.05倍.结果显示,ThBADH基因可能参与了刚毛柽柳对NaCl和PEG6000胁迫响应过程,但其功能仍需进一步验证.

Betain ealdehyde dehydrogenase(BADH)is a key enzyme in the biosynthesis of betaine.BADH plays an important role in plant response to abiotic stresses by regulating plant physiological and biochemical processes.In this study,a novel BADH gene(ThBADH)was cloned from Tamarix hispida by RT-PCR.The opening reading frame(ORF)length of ThBADH was 1 512bp,encoding 503 amino acid.The relative molecular weight of ThBADH protein was 54.58kD,with isoelectric point 5.21.And the expression patterns of ThBADH gene in the leaves and roots of Tamarix hispida were analyzed by qRT-PCR under different stress treatments.The results of qRT-PCR showed that the expressions of ThBADH gene were different under hormone treatments and abiotic stresses compared the control.Specifically,expression of ThBADH was examined in the leaves and roots of Tamarix hispida,but not or only slightly expressed in leaves and roots under the hormone treatment(100μmol/L JA,50μmol/L GA3and 100μmol/L ABA).However,the expressions of ThBADH were induced in the Tamarix hispida after NaCl and PEG6000 stresses with a maximum upregulation of 90.51-fold and 30.05-fold in contrast to the control material,respectively.The results indicated that the ThBADH gene may be involved in the high salt and drought stress in Tamarix hispida,but the functions still need further verification.