Cloning and Functional Analysis of WRKY77 gene in poplar

• 1、School of Forestry and Landscape Architecture, Anhui Agricultural University,Hefei 230036

Abstract：WRKY gene family members broadly involve in a series of plant physiological activities, for example, responses to environmental stresses, plant growth and development, metabolic regulation and plant defense responses to distinct pathogens. In this research, we cloned PtrWRKY77 gene from Populus deltoids cv. Nanlin 95. Possessing coding region of of 969 bp, this gene encodes 322 amino acids. Besides the predictive coding protein contains one WRKY domain and one C2HC zinc finger motif. Phylogenetic analysis showed that PtrWRKY77 was closed to one disease resistance related gene AtWRKY70. Sequence analysis indicated that PtrWRKY77 was highly similar to AtWRKY70 in gene structure and conserved motif; cis-element analysis showed that PtrWRKY77 obtained fungal elicitor responsive element and cis-acting element involved in defense and stress responsiveness. Tissue expression pattern analysis found PtrWRKY77 had high expression quantity in differentiating xylem. PtrWRKY77 was obviously induced by SA with highest gene expression, followed by wounding, But PtrWRKY77 gene expression of MeJA treatment is not obviously elevated; gene expression with two mixed rust pathogens treatment is higher than the it of individual rust pathogen treatment. Subcellular localization experiment showed that PtrWRKY77 located in the nucleus. Yeast hybrid assays exhibited that PtrWRKY77 owned transcription activity. Overexpression PtrWRKY77 in "Nanlin 95" could raise the SA level of transgenic plant.

Keywords： poplar PtrWRKY77 subcellular localization transcriptional activity genetic transformation