In-silico characterization of drought stress related WRKY2 transcription factor in wheat crop ( Triticum aestivum L.): study of its physico-chemical properties and structural dynamics

Plant growth and response to various stresses are facilitated by the WRKY protein family, and is recognized as one of the most extensive families of transcription factors (TFs) in the plant kingdom. The importance of WRKY in plant defense mechanism and its interaction with defense hormones are well-known in wheat, however, data on its structural and conformational features are lacking in wheat. The current study revealed that TaWRKY2 is largely conserved at the amino acid level, but has undergone various changes over evolution, likely to achieve the diversified function. A novel motif (WRKYGQK) in wheat and other related species was identified. Two WRKY domains were found in the TaWRKY2 protein. The protein was found to have 468 amino acid residues, non-polar and basic in nature with pI 8.56 and with more positively charged amino acids. It is highly unstable as the instability index was > 40. Out of 3 motifs,2 was having WRKYGQK conserved sequence. There was a significant amount of phosphorylation seen on threonine and serine residues of TaWRKY2 . The predicted secondary structure had 4-β-strand, 7-β-turns, 2-γ-turns, and 3-beta hairpins. The homology-based analysis of TaWRKY domains provided adequate Ramachandran statistics and satisfied all the required energy parameters. This protein’s structural characterization will aid in understanding its molecular mode of action. These in-silico analyses provide a better knowledge of the WRKY TFs in wheat and other related species under environmental stress conditions, and increasing the number of these WRKY s would aid in the molecular breeding of tolerant wheat cultivars.