海马齿Na^+/H^+逆转运蛋白基因SpNHX1的克隆及表达模式  

Isolation and Expression Analysis of Na^+/ H^+ Antiporter Gene SpNHX1 from Sesuvium portulacastrumand L.

作　　者：喻珊[1] 胡艳平 丛心黎 周扬 江行玉[1] 

机构地区：[1]海南大学农学院,海南海口570228 [2]海南省农业科学院蔬菜研究所,海南海口571100 [3]农业部热带作物生物学与遗传资源利用重点实验室,海南海口571101

出　　处：《热带生物学报》2015年第2期127-133,共7页Journal of Tropical Biology

基　　金：国家自然科学基金项目(31260218);海南省自然科学基金项目(313030);海南大学科研启动项目(Kyqd1205)

摘　　要：从盐生植物海马齿中克隆了Na+/H+逆转运蛋白基因SpNHX1,生物信息学分析结果表明,Sp NHX1蛋白与拟南芥At NHX1和At NHX2的相似度分别达到了76.35%和77.12%,从而推测,SpNHX1可能具有与At NHX1和At NHX2相似的功能,能将Na+区隔到液泡中,提高植物耐盐性。采用荧光定量PCR的方法,对SpNHX1基因在4种胁迫(600 mmol·L-1Na Cl胁迫、100μmol·L-1ABA胁迫、4℃低温胁迫、20%PEG6000干旱胁迫)下的表达量进行了研究。结果表明:SpNHX1基因在根和茎中受盐胁迫诱导上调表达,叶中表达量变化较小;而在ABA胁迫、4℃低温胁迫、20%PEG6000干旱胁迫下,SpNHX1基因的表达受胁迫影响较小,且没有规律性。说明SpNHX1基因的表达与其耐盐性相关,且表达具有组织特性。A Na^＋/H ^＋ antiporter gene SpNHX1 from Sesuvium portulacastrumand L. was cloned by using PCR methods. Bioinformation analysis showed that SpNHX1 shared higher identity with AtNHX1 （76.35%） and At- NHX2 （77.12%）, which indicated that the protein SpNHX1 might have similar function as AtNHX1 and At- NHX2 that compartmentalize excessive Na^＋ into vacuole, thus improving plant salt tolerance. Real-time PCR was used for identification of the expression levels of the gene SpNHX1 under 4 different stress treatments, 600 mmol · L^-1 NaCl, 100 μmol · L^-1 ABA, low temperature at 4℃, and 20% PEG6000 drought stress. The gene SpNttX1 was up-regulated in the roots and stems other than in leaves under salt stress. Hardly clear expression tendency of SpNHX1 was observed under 100 μmol · L^-1 ABA, low temperature at 4℃, and drought stress. These illustrated that the expression of the gene SpNHX1 was related to plant salt tolerance, and its expression was tissue-specific.

关 键 词：海马齿 Na+/H+逆转运蛋白 SpNHX1 耐盐性 基因表达 

分 类 号：Q781[生物学—分子生物学] Q786