辣椒C基因全长序列比较分析

辣/甜椒C基因测序比对后证实了甜椒C基因5′端约689 bp的缺失可能是造成其辣味缺失的原因。牛角形甜椒‘0538’的C基因不存在这一缺失, 却在编码区第40位碱基处有一个G到A的突变,可能导致信号肽内第14位疏水性天冬氨酸变为亲水性天冬酰胺, 不能完成辣椒素的合成, 最终辣味缺失。辣/甜椒品种共有长片段Catf2基因, 与C基因在核苷酸序列上有88.9%的相似性。

Comparison and Analysis of C Gene from Different Pepper Accessions

Deletion of 689 bp in 5'-terminal of the C gene locus caused an absence of pungency in sweet pepper after sequencing and alignment.A C gene fragment from non-pungent oxhorn pepper 0538 was amplified,which does not have the deletion,but a mutation from G to A at 40 bp in the coding region.This mutation led to the change of an amino acid from hydrophobic aspartic acid to hydrophilic asparaginate in signal peptide,which might cause the loss of the function of the C gene and finally the pungency.Using the same primer pair,Catf2 gene from all used accessions was amplified,which shares high similarity about 88.9% with the C gene.