辣椒CaCNGC4基因克隆及表达分析OA

Cyclic nucleotide gated ion channels(CNGCs)plays an extremely important role in various physiological processes of plants,including signal transduction,growth and development,and responses to environmental stress.This study cloned the CaCNGC4 gene from peppers(Capsicum annuum)and performed bioinformatics analysis,expression pattern analysis,and subcellular localization analysis of CaCNGC4.The results showed that the CDS sequence of CaCNGC4 was 2 091 bp and encoded 696 amino acids.It was an alkaline and unstable hydrophilic protein with 6 transmembrane structures,a signal-free peptide,and the subcellular localization results showed that it was located on the plasma membrane.The CaCNGC4 protein had the highest homology with potato(Solanum tuberosum)and opium(S.dulcamara),which were 86.64%and 85.94%respectively,and the lowest homology with sweet potato(Ipomoea batatas),which was 70.07%.The expression level changes of CaCNGC4 gene under hormone(abscisic acid(ABA),gibberellin A3(GA3),methyl jasmonate(MeJA))treatment and abiotic stress(including high temperature,low temperature,and salt stress)during pepper development were detected by qPCR.The results showed that under hormone treatment and salt stress,the expression of CaCNGC4 gene first decreased,then increased,and finally decreased again.The expression of CaCNGC4 was significantly downregulated after high-temperature treatment for 1,1.5 and 3 h,while it was significantly upregulated under high-temperature treatment for 6,12 and 24 h(P＜0.05).The expression of CaCNGC4 was significantly downregulated after low-temperature treatment(P＜0.05),with no significant difference compared to the control at 24 h.The promoter region of this gene contained a series of cis-elements related to light response,hormone,external environment,and growth and development.The results of this study provide theoretical support for the regulation of pepper growth and development and the improvement of pepper varieties.