摘要
以栽培烟草‘云烟87’为材料,通过同源克隆方法分离了烟草NHX(Na+,K+/H+exchanger)基因NtNHX1-3。结果表明:NtNHX1-3基因CDS长度1 617bp,编码蛋白质长度为538aa,蛋白理论等电点为8.67,分子量为59.34kD。预测NtNHX1-3属于膜蛋白,含有11个跨膜区,且含有NHX类蛋白保守位点氨氯吡嗪咪结合位点。进化树分析显示,NtNHX1-3与菊苣、野菊花NHX遗传距离最近。qRT-PCR组织特异性表达分析表明,NtNHX1-3在烟草叶片中表达量最高,根、茎、花中也有表达;盐胁迫处理后NtNHX1-3基因的表达上调,表明该基因参与了盐胁迫反应;打顶初期NtNHX1-3基因的表达呈逐渐上调的趋势,与该时期钾含量逐渐升高相吻合。研究推测,NtNHX1-3具有将钾离子从细胞质转运至液泡的功能。
The NtNHX 1-3 gene was successfully isolated by homologous cloning from cultivated tobacco. The CDS length of NtNHX 1-3 was 1 617 bp, and it was predicted to encode a 538-amino acid protein. The theoretical isoelectric point of NtNHX1-3 protein was 8.67, and the molecular weight was 59.34 kD. The bioinformation analysis of NtNHX1-3 showed that it belonged to membrane protein containing 11 transmembrane regions,and had a conserved amiloride binding-site specific to NHX protein. The phylogenetic tree analysis showed that NtNHX1-3 shared the same group with NHX from chicory and chrysanthemum. Tissue-specific expression analysis indicated that NtNHX 1-3 was ubiquitously expressed in roots, stems, leaves and flowers, whereas had the highest level in leaves. The expression of NtNHX 1-3 was up-regulated after salt treatment, indicating that it was involved in salt stress response. The expression of NtNHX 1-3 was up-regulated in the early stage of topping, which was consistent with the increase of potassium content in this stage. Therefore, it was speculated that NtNHX1-3 could transport potassium ions from cytoplasm to vacuole.
作者
高玉龙
宋中邦
李梅云
李文正
王丙武
李永平
GAO Yulong;SONG Zhongbang;LI Meiyun;LI Wenzheng;WANG Bingwu;LI Yongping(Yunnan Academy of Tobacco Agricultural Sciences, Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Kunming 650021, China)
出处
《西北植物学报》
CAS
CSCD
北大核心
2018年第12期2201-2206,共6页
Acta Botanica Boreali-Occidentalia Sinica
基金
中国烟草总公司云南省公司科技计划(2016YN26).
