灰绿藜液泡膜焦磷酸酶基因的克隆及表达分析

采用同源克隆的方法,获得盐生植物灰绿藜的液泡膜焦磷酸酶基因(VP1)全长cDNA,命名为CgVP1。生物信息学预测分析表明,CgVP1基因包含一个2 292bp的开放阅读框,编码763个氨基酸。CgVP1不仅具有与植物液泡膜焦磷酸酶共有的氨基酸序列DVGADLVGKVE,而且CgVP1与其它植物的VP1相似性达86%。跨膜结构域预测显示,CgVP1氨基酸序列含有12个跨膜螺旋区,可能定位于细胞膜系统上。RT-PCR检测表明,200mmol/L NaCl条件下萌发生长的灰绿藜,再进行800mmol/L NaCl胁迫处理24h后,CgVP1基因表达显著增强。不同浓度KCl、CaCl2、MgCl2分别处理24h,KCl和MgCl2浓度增高,CgVP1基因表达下降,CaCl2则不影响CgVP1基因表达。研究结果表明,灰绿藜CgVP1基因表达对不同种类盐胁迫响应不同,NaCl胁迫可以上调CgVP1基因表达。该研究结果有助于阐明盐胁迫对盐生植物灰绿藜CgVP1基因表达的调控作用。

Clone and Expression Analysis of the Vacuolar Pyrophosphatase Gene from Chenopodium glaucum

The full-length cDNA of the vacuolar pyrophosphatase(VP1) from halophyte Chenopodium glaucum was cloned by using RACE technique,and was named as CgVP1.It contained a 2 292 bp open reading frame (ORF) encoding 763 amino acid polypeptide.This sequence of CgVP1 contained DVGADLVGKVE,a consensuses sequence in plant VP1 proteins.CgVP1 shared more than 86% similarity with VP1s from other plants.Transmembrane domain prediction showed that CgVP1 contained 12 trans-membrane helix regions,and sub-cellularly localized in cellular membrane system.RT-PCR results showed that when C.glaucum was treated with 200 mmol/L NaCl during the germination and growth,and then treated with 800 mmol/L NaCl for 24 h,the expression of CgVP1 gene was significantly increased compared to the control which was not pre-treated with 200 mmol/L NaCl.When C.glaucum was treated with different concentrations of KCl,CaCl₂ and MgCl₂ for 24 h,respectively,the expression of CgVP1 was down regulated with the increase of the concentrations of KCl and MgCl₂,whereas CaCl₂ did not influence the expression of CgVP1.These results indicated that the expressions of CgVP1 response differentially to different types of salt treatments,and NaCl stress can induce its expression.This study can help to understand the regulatory function of VP1 in halophyte C.glaucum under salt stress.