不同青熟果色线辣椒中APRR2基因的克隆与表达分析

Cloning and expression analysis of APRR2 gene in chili pepper with different immature fruit colors

青熟果色是辣椒重要的商品性状之一,为探究拟南芥伪响应调节因子基因(APRR2)对青熟果色的影响,本研究以青海地方品种循化线辣椒深绿青熟果色野生型XHB及浅绿青熟果色突变体QL2017为研究材料,对不同青熟果色线辣椒中的基因APRR2进行克隆和时空表达分析。结果表明:APRR2基因CDS序列全长为1737 bp,共编码578个氨基酸,在XHB和QL2017中序列没有差异;APRR2蛋白分子质量64.34 kDa,等电点5.74,为不稳定亲水性蛋白,属于SANT超家族;在系统进化关系上,线辣椒APRR2蛋白与茄科的番茄和潘那利番茄同属一个分支;APRR2基因在2个品种不同时期不同组织中的表达存在显著差异,且具有组织特异性。APRR2基因在XHB果实、QL2017叶和果实中的表达量显著高于其他组织,在茎中表达量最低。研究结果为后续相关基因定位及深入分析线辣椒青熟果色形成机制提供了理论依据。

Immature fruit color is one of the important commercial traits of Capsicum annuum L.In order to explore the effects of Arabidopsis pseudo response regulator gene(APRR2)on the imma-ture fruit color,Qinghai local variety Xunhua chili pepper dark green immature fruit color wild type XHB and light green immature fruit color mutant QL2017 are taken as research materials to clone and analyze the spatial and temporal expression of APRR2 gene with different immature fruit colors of Capsicum annuum L.The results show that the full-length of CDS sequence of APRR2 gene is 1737 bp,encoding 578 amino acids.There is no difference between XHB and QL2017 sequences.The APRR2 protein has a molecular weight of 64.34 kDa and an isoelectric point of 5.74.It is an unstable hydrophilic protein,which belongs to SANT superfamily.In terms of systematic evolutionary relationship,APRR2 protein of chili pepper belongs to the same branch as Solanaceae tomato and Panari tomato.The expressions of APRR2 gene are significantly different in different tissue of the two varieties at different stages with tissue specificity.The expression levels of APRR2 gene in XHB fruit,QL2017 leaf and fruit are significantly higher than that in other tissue,while the expression level in stem is the lowest.The results can provide a theoretical basis for subsequent related gene mapping and in-depth analysis of formation mechanism of immature fruit colors of chili pepper.