Comprehensive analysis and identification of drought-responsive candidate NAC genes in three semi-arid tropics (SAT) legume crops

Abstract Background Chickpea, pigeonpea, and groundnut are the primary legume crops of semi-arid tropics (SAT) their global productivity is severely affected by drought stress. The plant-specific NAC (NAM - no apical meristem, ATAF Arabidopsis transcription activation factor, CUC cup-shaped cotyledon) factor family known to be involved in majority abiotic stresses, especially stress tolerance mechanism. Despite knowledge available regarding function, not much information on genes SAT crops. Results In this study, genome-wide proteins – 72, 96, 166 have been identified from genomes chickpea, groundnut, respectively, later grouped into 10 clusters chickpea while 12 groundnut. Phylogeny with well-known stress-responsive NACs thaliana , Oryza sativa (rice), Medicago truncatula Glycine max (soybean) enabled prediction putative (22), pigeonpea (31), (33). Transcriptome data revealed at various developmental stages that showed differential expression patterns different tissues studied. Quantitative real-time PCR (qRT-PCR) was performed validate selected stress-responsive, Ca_NAC ( Cicer arietinum 14) Cc_NAC Cajanus cajan 15) Ah_NAC Arachis hypogaea using drought-stressed well-watered root two contrasting drought-responsive genotypes each three legumes. Based analysis, Ca_06899, Ca_18090, Ca_22941, Ca_04337, Ca_04069, Ca_04233, Ca_12660, Ca_16379, Ca_16946, Ca_21186 ; Cc_26125 Cc_43030 Cc_43785 Cc_43786 Cc_22429 Cc_22430 Ah_ann1.G1V3KR.2 Ah_ann1.MI72XM.2 Ah_ann1.V0X4SV.1 Ah_ann1.FU1JML.2 Ah_ann1.8AKD3R.1 were as potential candidate genes. Conclusion As play role several physiological biological activities, a more comprehensive study identification analyses carried out We total 21 these These displayed correlation between gene expression, transcriptional regulation, better against drought. genes, after validation, may serve useful resource for molecular breeding