玉米自交系干旱应答基因的鉴定(英文)  

Identification of Drought-responsive Genes from Maize Inbred Lines

作　　者：李富华[1] 付风玲[1] 沙莉娜[1] 李晚忱[1] 

机构地区：[1]四川农业大学玉米研究所/西南作物基因资源与遗传改良教育部重点实验室,四川雅安625014

出　　处：《植物生理与分子生物学学报》2007年第6期607-611,共5页Journal Of Plant Physiology and Molecular Biology

基　　金：国家自然科学基金项目(No.30571172);Rockefeller基金项目(No.2004 FS 047);教育部长江学者和创新团队发展计划项目(No.IRT0453)资助。

摘　　要：为开发耐旱分子选择标记提供有用信息,用mRNA差异显示技术分离耐旱玉米自交系‘81565’在干旱胁迫与灌溉对照之间差异表达的基因,发现MD1、MD2和MD3二个在干旱胁迫下差异表达的片段。MD1和MD2为下调表达,MD3为上调表达。序列分析和同源性比对表明,MD1与编码成熟酶的玉米叶绿体基因matK有97%的相似性,MD2与极端耐旱植物Sporobolus stapfianus编码丝氨酸/苏氨酸蛋白磷酸酶的PP2C基因有99%的相似性,MD3与属精氨酸/赖氨酸特异性半胱氨酸蛋白酶类的水稻metacaspase酶基因有99%的相似性。根据MD2片段序列,结合电子克隆和RT-PCR方法,克隆出一条1731 bp的全长cDNA序列,它编码388个氨基酸。此氨基酸序列包含丝氨酸/苏氨酸蛋白磷酸酶2C的催化中心结构域,被认定为玉米PP2C基因族的新成员,命名为ZmPP2Ca。实时荧光定量PCR结果表明,在干旱胁迫下,ZmPP2Ca基因在3个耐旱自交系中呈下调表达,在2个不耐旱自交系中呈上调表达。To provide a useful piece of information for the choice of molecular markers to be used in selection of drought tolerance, mRNA differential display was used to isolate genes from a drought-tolerant maize inbred line ＇81565＇. After drought stress, two down-regulated expression gene fragments （MD1 and MD2） and one upregulated expression fragment （MD3） were obtained. Results of sequence and homology analysis show that MD1 has 97% similarity with matK in maize chloroplast genome, a gene encoding RNA maturase involved in group Ⅱ intron splicing of RNA transcript; MD2 has 99% similarity with the gene serine / threonine phosphory- lase 2C in Sporobolus stapfianus; and MD3 has 99% similarity with rice the gene encoding metacaspase, an arginine / lysine-specific cysteine protease. Based on the sequence of fragment MD2, a new member of maize PP2C gene family, ZmPP2Ca, was cloned by in silicon cloning and reverse transcription polymerase chain reaction （RT-PCR）. Real-time fluorescence quantitative polymerase chain reaction （FQ-PCR） showed that expression of the gene was down-regulated in the three droughttolerant lines （＇81565＇, ＇N87-1＇ and ＇R09＇） and up-regulated in the two drought-sensitive lines （＇200B＇and ＇ES40＇） under drought stress.

关 键 词：mRNA差异表达 玉米 干旱胁迫 丝氨酸 苏 氨酸蛋白磷酸酶2C ZmPP2Ca 实时荧光定量PCR 

分 类 号：S513[农业科学—作物学] Q943[生物学—植物学]