The TIFY Gene Family in Wheat and its Progenitors: Genome-wide Identification, Evolution and Expression Analysis

Background: The TIFY gene family is a group of plant-specific proteins involved in the jasmonate (JA) metabolic process, which plays a vital role in plant growth and development as well as stress response. Although it has been extensively studied in many species, the significance of this family is not well studied in wheat. Objective: To comprehensively understand the genome organization and evolution of TIFY family in wheat, a genome-wide identification was performed in wheat and its two progenitors using updated genome information provided here. Results: In total, 63, 13 and 17 TIFY proteins were identified in wheat, Triticum urartu and Aegilops tauschii respectively. Phylogenetic analysis clustered them into 18 groups with 14 groups possessing A, B and D copies in wheat, demonstrating the completion of the genome as well as the two rounds of allopolyploidization events. Gene structure, conserved protein motif and cis-regulatory element divergence of A, B, D homoeologous copies were also investigated to gain insight into the evolutionary conservation and divergence of homoeologous genes. Furthermore, the expression profiles of the genes were detected using the available RNA-seq and the expression of 4 drought-responsive candidates was further validated through qRT-PCR analysis. Finally, the co-expression network was constructed and a total of 22 nodes with 121 edges of gene pairs were found. Conclusion: This study systematically reported the characteristics of the wheat TIFY family, which ultimately provided important targets for further functional analysis and also facilitated the elucidation of the evolution mechanism of TIFY genes in wheat and more.