Genome-Wide Identification and Analysis of GHMP Kinase Gene Superfamily in Bread Wheat (Triticum aestivum L.)

The GHMP (galactokinase, homoserine kinase, mevalonate kinase and phosphomevalonate kinase) kinase gene superfamily is a unique class of ATP-dependent enzymes. It plays a role in the metabolism of carbohydrate, biosynthesis of isoprenes, amino acids and nucleotide sugars. However, this important gene family has not been characterized in wheat (Triticum aestivum L.). In this study, total forty-seven putative GHMP kinase sequences were identified in wheat (Triticum aestivum L.) genome. Physicochemical properties, motif prediction, conserved domain and exon-intron configuration analyses revealed that these sequences were distributed in 10 subfamilies. Promoter analysis of GHMP kinase sequences showed that the cis-acting regulatory elements are involved in diverse functions such as light, stress, hormone and metabolism responsiveness, tissue-specific activation, circadian control, binding site and cell cycle regulation. Phylogenetic relationship with other monocot species has further strengthened the subfamily grouping pattern. The heat map presented by transcriptomic data analysis revealed that 25 and 12 genes showed significant differential expression against the abiotic and biotic stresses, respectively. The expression of selected genes was validated under abiotic stress conditions viz., heat, drought and their combination by qRT-PCR analysis. In conclusion, the present study provides novel information, thus enhances our understanding of the GHMP kinase gene family in wheat. The information obtained will be valuable in selecting potential candidate genes in wheat for developing cultivars with improved tolerance against biotic and abiotic stresses.