Characterization and Interacting-Protein Identification of Cold-Responsive MaWRKY11 from Banana Fruit

Abstract:

In the present study, one WRKY transcription factor, designated as MaWRKY11, was isolated and identified from Digital Gene Expression Data (DGE) of banana fruit. MaWRKY11 contains double WRKY conserved domains and belongs to Group I of WRKY family. Subcellular localization indicated that MaWRKY11 was exclusively localized in the nucleus, implying that it was a nuclear protein. Transactivation assay showed that MaWRKY11 possessed transcriptional activity in yeast cells and the transcriptional domain located at its N-terminus. Moreover, real-time quantitative PCR displayed that MaWRKY11 was induced by chilling stress, and MeJA treatment which could alleviate chilling injury of banana fruit, up-regulated the expression of MaWRKY11. In addition, C-terminus of MaWRKY11 was used as a bait to screen its potential interacting proteins by using yeast two-hybrid system, and it was found that MaWRKY11 could interact with Early Responsive to Dehydration Protein, MaERD, which was also induced by cold. Taken together, these results suggest that MaWRKY11 might respond to chilling stress through interacting with stress-related proteins, such as MaERD.

Key words:banana fruit; WRKY; chilling stress; interacting protein