摘要
金属耐受蛋白MTP(metal tolerance protein)是阳离子转运蛋白(CDF)家族的重要成员,在植物重金属转运过程中发挥重要调控作用。本研究以中茶108茶树为试验材料,通过RT-PCR和RACE方法克隆到茶树重金属耐受蛋白基因CsMTP11(Gen Bank登录号为KX450265),其全长c DNA为1197 bp,编码398个氨基酸残基,其编码蛋白分子量为44.85 k D,等电点为5.34。在线软件分析表明,CsMTP11蛋白具有5个跨膜结构域,且含有CDF家族的其他保守结构域。系统进化树分析结果表明,茶树CsMTP11与葡萄VvMTP11进化同源性最近,其氨基酸序列相似度高达90%。基因表达模式分析表明,CsMTP11基因在茶树老叶中的表达量最高,根中的表达量最低,另外,CsMTP11基因受重金属Mn和Co离子胁迫诱导表达。CsMTP11-YFP融合蛋白在拟南芥原生质体共定位试验表明,CsMTP11-YFP融合蛋白定位于质膜。CsMTP11在酿酒酵母及其突变株中的异源表达可以提高其对重金属Mn和Co离子的耐受性。综上所述,茶树CsMTP11属于Mn-CDF亚家族,可能参与茶树对重金属锰和钴的转运过程。
As a member of cation diffusion facilitator family, metal tolerance protein（MTP） is involved in the regulation of heavy metal stress process in plant. Here, we cloned a MTP gene, CsMTP11（Gen Bank accession number： KX450265） from Zhongcha 108 tea plant. The full-length c DNA of CsMTP11 is 1197 bp, and the gene encodes a novel protein of 398 amino acids, which shares significant sequence similarity with VvMTP11（90%）. The molecular weight and theoretical p I of this protein are 44.85 k D and 5.34, respectively. The conserved domain analysis indicated that CsMTP11 contained five transmembrane domains and the conserved CDF domain. The phylogenetic tree indicated that CsMTP11 had sequence conservation among different species. The transcriptional level of CsMTP11 in old leaf was higher than that in root. Futher more, the heavy metal Mn and Co stresses induced the expression of CsMTP11. The subcellular localization assay using CsMTP11-YFP fusion gene expressed in the Arabidopsis protoplast showed that CsMTP11 was localized in the plasma membranes. CsMTP11 heterologous expression in wild-type yeast BY4741 and the mutants showed that it was able to increase tolerance to Mn and Co. Taken together, our results indicated that CsMTP11 is a member of the Mn-CDF family, and it may be involved in the regulation of heavy metal stress process in tea plant.
出处
《作物学报》
CAS
CSCD
北大核心
2017年第5期708-717,共10页
Acta Agronomica Sinica
基金
国家自然科学基金项目(31400583)
重庆市基础与前沿研究计划一般项目(cstc2014jcyjA80011)
中央高校基本业务费专项(XDJK2014C070)资助~~
关键词
茶树
重金属耐受蛋白
基因克隆
锰
Camellia sinensis
Heavy metal tolerance
Gene clone
Mn
