盐胁迫对拟南芥AtPUB18基因的诱导表达及其启动子分析

用300mmol/L NaCl处理拟南芥幼苗,分别于处理后0、1、2、4、8、16、24、48h通过Northern Blot检测其AtPUB18基因的表达量。结果显示:拟南芥AtPUB18基因的表达量受高盐胁迫的诱导而升高,于处理后4h表达量达到最高,处理后16h表达量最低。采用PCR技术克隆AtPUB18的启动子,序列为1 974bp;序列分析发现启动子内含有大量与非生物胁迫相关的顺式作用元件,如HSE、LTR、MBS及ABRE;将启动子克隆到表达载体pCambia1300-221-GUS中,驱动报告基因GUS表达。组织化学染色结果表明,未经过高盐处理的幼苗中GUS基因表达水平很低;300mmol/L NaCl处理后GUS基因表达量显著升高。研究表明,AtPUB18的表达受高盐胁迫诱导,且AtPUB18基因的启动子是一个盐胁迫诱导型启动子。

Expression of AtPUB18 after Salt Stress Treatment and Analysis of Its Promoter from Arabidopsis thaliana

Young seedlings were treated by 300 mmol/L NaCl and harvested after being treated for 0,1,2,4,8,16,24 and 48 hours for RNA extraction.Northern Blot was performed to check the expression of AtPUB18.The result showed that the expression was induced by high salinity stress and reached the peak after treatment for 4 h followed by decreasing to the lowest level after 16 h treatment.PCR was performed to clone the promoter of AtPUB18 which is composed of 1 974 bp.Analysis of the sequence of this promoter displayed that many cis-elements associated with abiotic stress localized in promoter,such as HSE,LTR,MBS and ABRE.The promoter were cloned into pCambia1300-221-GUS to drive the expression of GUS.Histochemical staining revealed that the expression level of GUS without salt treatment was very low,but the expression of GUS became much stronger after 4 h of 300 mmol/L NaCl treatment.Our results manifested that the expression of AtPUB18 can be induced by salt stress and the promoter of AtPUB18 is a high salinity-induced promoter.