Molecular Cloning, Sequence Analysis and Expression Analysis of an NtWRKY6 from Tobacco (Nicotiana tabacum L.) in Abiotic Strsss

Liqin Li, Yubi Huang, Wei Wang, Yaling Xu

College of Agronomy, Sichuan Agricultural University, Chengdu, China.
College of Agronomy, Sichuan Agricultural University, Chengdu, China..

DOI: 10.4236/ajps.2012.311183                

Abstract

In higher plants, WRKY gene family plays a significant role in transcriptional regulation. They are widely involved in biotic stress, abiotic stress, growth, development and metabolism regulation. In this study WRKY6 from tobacco is cloned by homology cloning. 1647 nucleotide sequences were obtained. The deduced protein sequences show that this protein belongs to the second group of WRKY family, only have one WRKY structure, and the zinc-finger structure is C-X₄-C-X₂₃-H-X₁-H. Phylogeny results show NtWRKY6 is much closer to NtWRKY1 generated 97% amino acids similarity. RT-PCR analysis has revealed that expression levels of NtWRKY6 has increased rapidly at 3 h under NaCI and PEG treatment. The results suggest that NtWRKY6 is an early responder and may be involved in NaCl and PEG abiotic stress in tobacco.

Keywords

WRKY Protein; Molecular Cloning; Tobacco; RT-PCR; Expression Analysis

Conflicts of Interest

The authors declare no conflicts of interest.

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