‘阿蒂擎天’凤梨谷胱甘肽-S-转移酶基因的克隆与乙烯诱导表达特性的初步分析

Cloning of Glutathione-s-transferase Gene and Primary Expression Analysis in Guzmania wittmackii ‘Attila’ Induced by Ethylene

以阿蒂擎天凤梨乙烯处理和不处理的植株为材料建立的抑制性差减杂交文库中,筛选到的一个被乙烯诱导并与已知植物谷胱甘肽-S-转移酶(GST)同源的cDNA片段,通过RACE技术得到该基因的全长cDNA序列。序列分析表明,该基因可能属于thioredoxin-likesuperfamily和GSTC_family superfamily两个超家族中的成员。利用半定量RT-PCR检测该基因的表达量在乙烯处理后先会在1h显著升高,然后随时间逐步降低,说明乙烯作为一种逆境胁迫相关激素,可在短时间内诱导凤梨中GST的表达。推测其在受到外源乙烯信号诱导后,一方面可能参与了植物体内的解毒作用,另一方面可能参与了花青素的合成调控和运输。本实验中的GST作为观赏凤梨中一个新发现的GSTs家族成员,对于研究热带花卉中GSTs家族的特点和提高其抗逆性和品质具有重要的理论意义和实用价值。

An ethylene inducible eDNA fragment being homology with the known glutathione-s-transferase （GST） in plants was screened in the suppression subtractive hybridization （SSH） library constructed with the materials of Guzmania wittmackii Attila plant treated and untreated by ethylene. Rapid Amplification of eDNA Ends （RACE） was used to obtain the full length eDNA. Sequence analysis suggested that the gene should belong to thioredoxin- like superfamily and GST C_family superfam＇ily. Semi-quantitative RT-PCR results exhibited that the expre ssion of this gene significantly increased with the treatment of ethylene in one hour, and then decreased gradually with time, which suggested that the ethylene as an adversity stressrelated hormone could induce GST gene expression in a short time. We hypothesized that GST, on the one hand, might be involved in detoxification in vivo, on the other hand, might be involved in regulation and transport of anthocyanin after ethylene induction. In our research, this GST as one new member of GSTs family in bromeliads, has the essential theoretical significance and applied value to study GSTs family characteristics and improve stress resistance and quality modification in tropical flowers.