甜椒甘油- 3 - 磷酸酰基转移酶基因的克隆与表达分析

 用RT-PCR技术从甜椒(Capsicum annuum ) 中克隆了甘油- 3 - 磷酸酰基转移酶基因的cDNA序列, 其全长为1 791 bp, 开放阅读框架为1 392 bp, 编码463个氨基酸, 命名为CaGPAT。序列分析表明该基因与番茄中的甘油- 3 - 磷酸酰基转移酶基因同源性最高; 在进化上与番茄最先聚类, 其次是菠菜。Northern杂交结果显示, CaGPAT在甜椒各器官中表达量差异较大, 叶片中的表达量明显高于根、茎、花及果实。低温诱导该基因快速表达, 8℃下处理3 h该基因表达量最高, 12 h以后基因表达量下降; 而高温对基因表达没有明显影响。当温度低于15℃时基因表达被诱导。结果表明甜椒叶绿体CaGPAT的表达量与低温关系密切。

Cloning and Expression Analysis of Glycerol-3-phosphate Acyltransferase Gene from Sweet Pepper

A full length cDNA of glycerol-3-phosphate acyltransferase ( GPAT) gene was cloned from sweet pepper by using RT-PCR approach with degenerate primers based on the conserved motifs found in a number of p lant GPAT genes. The CaGPAT is 1 791 bp encoding 463 amino acids, with high homology to tomato GPAT gene. Phylogenetic tree analysis showed that the amino acid sequence of GPAT in sweet pepper first gathered with that in tomato, then with that in spinach. Northern blot showed that the exp ression of CaGPAT in leaves was higher than that in other organs such as roots, stems, petals and fruits. CaGPAT expression could be significantly induced by low temperature ( 8℃) for 3 h. But it could not be obviously induced by high temperature ( 35℃). The gene expression level had no obvious difference at 5℃, 10℃ and 15℃.These results demonstrate that CaGPAT expression is closely correlated with plant responding to low temperature.