摘要
以‘资阳’香橙(Citrus junos‘Ziyang’)为材料,利用RT-PCR技术,分离到1个MYB基因,CitMYB22。比对分析发现,CitMYB22含有两个内含子,开放阅读框(ORF)为696 bp,可编码231个氨基酸残基的多肽。氨基酸聚类和结构分析表明,CitMYB22属于MYB类转录因子家族中的R2R3-MYB亚家族。进化树分析表明,CitMYB22与拟南芥参与逆境响应的R2R3-MYB亚家族成员At MYB15的同源性最高。克隆CitMYB22的ATG上游2 500 bp内启动子顺式元件,预测其含有多个与植物逆境和激素应答相关的顺式作用元件,如HSE、SARE和MBS等。亚细胞定位结果显示CitMYB22蛋白定位在细胞核中。实时定量结果表明,CitMYB22在叶、花中的表达量明显高于根和幼果,且在外源脱落酸、水杨酸、甲基茉莉酸、1–氨基环丙烷基羧酸以及高盐、脱水和4℃低温等非生物逆境胁迫下,均被诱导上调表达,推测CitMYB22可能与‘资阳’香橙的抗逆性相关。
CitMYB22,an member of MYB family gene,was cloned using RT-PCR from leaf of Citrus junos Sieb. ex‘Ziyang＇. Comparison between c DNA and genomic DNA sequences showed that two introns were existed in CitMYB22 gene. The 696 bp length ORF of CitMYB22,encoding a putative protein of 231 amino acids. The conserved R2R3 domain was observed in the amino acid structure sequence of CitMYB22. Phylogenetic analysis revealed that CitMYB22 shared the highest amino acid identities with homologous Arabidopsis R2R3-MYB transcription factor At MYB15. A 2 500 bp long promoter of the CitMYB22 gene was isolated,sequence analysis showed that the promoter harbors multiple stressresponsive cis-elements,such as HSE,SARE and MYS. The green fluorescent protein transient expression assay revealed that the CitMYB22 protein was localized in nucleus location. q RT-PCR analysis indicated that the higher expression of CitMYB22 gene was in leaves and flowers than in roots and fruitlets. Moreover,CitMYB22 was induced by exogenous hormone abscisic acid（ABA）,salicylic acid（SA）,methyl jasmonate（Me JA）,1-amino cyclopropane carboxylate（ACC）and physiological stresses of salinity,dehydration and low temperature（4 ℃）in leaves and roots. The results demonstrated that CitMYB22 may play a positive role in abiotic stress tolerance of citrus.
出处
《园艺学报》
CAS
CSCD
北大核心
2016年第6期1057-1068,共12页
Acta Horticulturae Sinica
基金
国家自然科学基金项目(31501746)
中央高校基金项目(XDJK2015C015
XDJK2016B022)
重庆市自然科学基金项目(cstc2015jcyjj A80039)
