论文部分内容阅读
本研究根据Gene Bank已发表的辣椒基因组序列信息,设计引物,利用RT-PCR法从海南黄灯笼辣椒中克隆了多聚半乳糖醛酸酶基因(PG),并命名为CCa PG基因。生物信息学及表达分析结果表明,该基因CDS区全长1 107 bp,编码368个氨基酸,推测为稳定的亲水蛋白,在N端由一条长约25 aa的信号肽;CCa PG蛋白二级结构预测显示,α-螺旋占18.75%,延伸链占37.23%,无规则卷曲占36.41%,β-转角占7.61%。系统进化树分析结果显示,CCa PG与一年生辣椒的亲缘关系最近,达98.37%,其次为美花烟草76.16%。表达量分析发现,CCa PG基因在果实变色期表达量最高,其次为幼果期,最低为绿熟期。本结果可为研究该基因的生物学功能和黄灯笼辣椒果实软化的调控机制奠定理论基础。
In this study, primers were designed according to the genome sequence of pepper genome published by Gene Bank. The polygalacturonase gene (PG) was cloned from Hainan yellow lantern by RT-PCR and named as CCa PG gene. Bioinformatics and expression analysis showed that the CDS region of this gene was 1 107 bp in length and encoded a protein of 368 amino acids. It was presumed to be a stable hydrophilic protein with a signal peptide about 25 aa at the N-terminus. Structural prediction shows that α-helix accounted for 18.75%, extended chain accounted for 37.23%, random coil accounted for 36.41%, β-turn accounted for 7.61%. Phylogenetic tree analysis showed that the genetic relationship between CCa PG and annual peppers was the most recent, reaching 98.37%, followed by 76.16% of that of American tobacco. The expression analysis showed that CCa PG gene had the highest expression level during fruit discoloration, followed by young fruit and lowest green ripening. The results may lay a theoretical foundation for studying the biological function of this gene and the regulation mechanism of the fruits of yellow lantern pepper.