巴西橡胶树HbγGCS基因克隆及表达分析  

Cloning and Expression Analyses of γGCS Gene in Hevea brasiliensis Muell.Arg.

作　　者：邓治[1] 刘向红[1,2] 覃碧[1] 李德军[1] 

机构地区：[1]中国热带农业科学院橡胶研究所,农业部橡胶树生物学与遗传资源利用重点实验室,海南儋州571737 [2]海南大学农学院,海口570288

出　　处：《植物生理学报》2012年第8期772-778,共7页Plant Physiology Journal

基　　金：国家自然科学基金(30960310);海南省自然科学基金(807044);农业部橡胶树生物学重点实验室开放课题(KLOF0905)

摘　　要：γ-谷氨酰半胱氨酸合成酶(γGCS)是细胞内谷胱甘肽(GSH)生物合成的限速酶,GSH在植物许多生理过程中发挥重要作用。本研究采用简并PCR和RACE技术获得巴西橡胶树γGCS基因全长cDNA序列,命名为HbγGCS(GenBank登录号:GU997638)。该基因全长2187bp,最长开放阅读框为1572bp,编码523个氨基酸。进化分析结果表明HbγGCS属双子叶植物γGCS亚类,同葡萄γGCS分为一组,与单子叶植物的亲缘关系较远。半定量RT-PCR结果表明HbγGCS基因在胶乳、叶片、树皮、花中均有表达,以花中表达量最大。健康橡胶树胶乳中HbγGCS表达量高于死皮树。HbγGCS表达受乙烯、茉莉酸、过氧化氢、机械伤害、干旱、低温和高盐调控。γ-Glutamylcysteine synthetase （yGCS） is a rate-limiting enzyme in glutathione biosynthesis. Glutathione plays a key role in many important physiological processes of plant. In this study, a full-length cDNA sequence of 7GCS gene was obtained from the latex ofHevea brasiliensis with degeneracy PCR and RACE, and named as HbyGCS （GenBank accession No. GU997638）. The full length cDNA of HbγGCS was 2 187 bp in size, with a 1 572-bp open reading frame encoding a deduced polypeptide of 523 amino acids. The phylogenetic analyses indicated that HbγGCS belonged to the yGCS of dicot subclass. I3tis vinifera yGCS and HbγGCS were divided into one group. Compared with the monocot 3,GCSs, HbγGCS indicated closer phylogenetic relation- ship with dicot yGCSs. Semi-quantitative RT-PCR analysis indicated that HbyGCS was ubiquitously expressed in all tissues, with the highest expression in flowers. HbγGCS transcript level was significantly higher in latex of healthy rubber trees than tapping panel dryness （TPD） ones. The expression of HbyGCS was regulated by ethylene, iasmonic acid. H^O~. mechanical wounding, drought, low temnerature and NaC1 treatments.

关 键 词：Γ谷氨酰半胱氨酸合成酶 巴西橡胶树 基因克隆 表达分析 序列分析 

分 类 号：S794.1[农业科学—林木遗传育种]