Genome wide identification and analysis of inositol tetrakisphosphate kinase (ITPK) gene family in Triticum aestivum L.

Inositol tetrakisphosphates kinase ( ITPK ) plays a vital role in regulating cellular responses to abiotic stress, plant hormone signaling and various other aspects of plant growth and development. Additionally, it is also involved in phosphorous, inositol phosphate metabolism and synthesize phytic acid which is the main phosphorous storage form in seeds. While essential for plant physiology, high phytic acid levels reduce the bioavailability of minerals such as Fe and Zn, which impact nutritional quality negatively. Despite its importance, the ITPK gene family remains largely unexplored in bread wheat. In this study, we conducted a comprehensive genome-wide analysis, including phylogenetic analysis and expression profiling, of the ITPK gene family in wheat. We systematically examined gene structure, chromosomal distribution, motif and domain conservation, promoter analysis, synteny analysis, protein modeling and protein-protein interaction of ITPKs . A total of 15 ITPK genes have been identified in wheat ( T. aestivum ). The TaITPK genes were distributed on chromosome number 1, 4, 5 and 7 in all the three genomes A, B and D. Comparative phylogenetic analysis resolved four major groups, with wheat ITPK sequences represented in Groups I, III, and IV, whereas Group II contained no wheat sequence. The conserved domain and motif analysis showed the presence of Ins134_P3_kin domain at N-terminus and CPase_L_D2 in C-terminus of protein. String based protein interaction analysis suggested ITPK genes interact with Inositol polyphosphate multi kinase ( IPK1 ) and Inositol-pentakisphosphate 2 kinase ( IPK2 ) which were also involve in synthesis of phyti acid. Furthermore, in-silico expression analysis of ITPK genes revealed their preferential tissue-specific and growth stage expression, especially after anthesis of wheat. Preliminary qRT-PCR profiling of selected TaITPK genes revealed treatment-dependent relative expression patterns under FeSO 4 and ZnSO 4 supplementation. The current study has identified 15 ITPK genes present in hexaploid wheat genome. Their evolutionary, structural, and expression analyses provide a foundation for further functional characterization of this gene family in wheat.