Research on the response of SaWRKY7 gene to cadmium stress in Sedum alfredii Hance

doi:10.3969/j.issn.1000-2006.201810007

JOURNAL OF NANJING FORESTRY UNIVERSITY ›› 2019, Vol. 43 ›› Issue (03): 59-66.doi: 10.3969/j.issn.1000-2006.201810007

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Research on the response of SaWRKY7 gene to cadmium stress in Sedum alfredii Hance

WANG Ying^1,2, QIU Wenmin², LI He², HE Xuelian², LIU Mingying², HAN Xiaojiao², QU Tongbao^1*, ZHUO Renying^2*

1. College of Horticulture, Jilin Agricultural University, Changchun 130118, China; 2 Key Laboratory of Tree Breeding of Zhejiang Province, The Research Institute of Subtropical of Forestry, Chinese Academy of Forestry, Hangzhou 311400, China

Online:2019-05-15 Published:2019-05-15

Abstract

Abstract: 【Objective】 Cadmium is highly toxic to plants. WRKY transcription factors are widely involved in stress response, therefor we studied the stress response and resistance mechanism of cadmium induced WRKY gene.【Method】 Gene sequences were obtained by PCR from the cDNA library of Sedum alfredii. Bioinformatics was used to analyze the protein structure.The green fluorescent protein fusion protein was constructed for the subcellular localization analysis. The transcriptional activation activity was verified with yeast. The expression characteristics and tissue specificity of the gene were analyzed by qRT-PCR under cadmium stress. 【Result】 A new member of the family of WRKY transcription factor genes was obtained and named SaWRKY7. It contained a complete open reading frame, which was 1 011 base pairs in length, encoded 336 amino acids, and was a member of the Ⅱd family of WRKY genes. SaWRKY7 was found in the nucleus, is a nucleoprotein, and showed no transcriptional activation activity. SaWRKY7 was expressed in roots, stems and leaves of S. alfredii, with relatively high expression found in roots. SaWRKY7 showed a higher expression level in the rhizomes and leaves in the 0.5 h with 100 μmol/L cadmium treatment than that of the control, and then decreased gradually; thus, it belonged to the early induced expression gene. 【Conclusion】 SaWRKY7 is a member of the family of WRKY transcription factor genes, which is found in the nucleus and does not have transcriptional self-activation activity. SaWRKY7 gene expression was induced by cadmium stress during the early stages. Results showed that SaWRKY7 might play an important role in S. alfredii response to cadmium stress.

CLC Number:

Q945.78

WANG Ying, QIU Wenmin, LI He, HE Xuelian, LIU Mingying, HAN Xiaojiao, QU Tongbao, ZHUO Renying. Research on the response of SaWRKY7 gene to cadmium stress in Sedum alfredii Hance[J]. JOURNAL OF NANJING FORESTRY UNIVERSITY, 2019, 43(03): 59-66.

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Research on the response of SaWRKY7 gene to cadmium stress in Sedum alfredii Hance

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