Transcriptome wide identification and characterization of NAC Transcription factors in response to abiotic stress in Oxytenanthera abyssinica A.rich munro. Oxytenanthera abyssinica

NAC members which are found only in the plant kingdoms have distinct structures and diverse functions. NACs have a tremendous role in cell differentiation and expansion, and hormone signaling in response to various stress. Despite this importance, genome-wide analysis and expression profiling of the NAC gene family under abiotic stress remains elusive in Oxytenanthera abyssinica. In this study, from abiotic stress-induced transcriptome, a total of 220 O. abyssinica TFs having intact NAC DNA binding domain (PF01849) were identified through genome-wide analysis. For the identified NACs, functional annotation, protein property, phylogenetic relationship and expression profiling under abiotic stress was presented. Results unveiled the presence of significant variation in gene length, molecular weights and isoelectric points of NAC members. The expression level of randomly selected OaNACs was examined using qRT-PCR. The qRT-PCR results have confirmed the differential expression of selected genes. This informs the key role of NACs in regulating abiotic stress tolerances in O. abyssinica. As 142 of the 220 OaNACs are differentially expressed due to either drought or salinity stress and most importantly the expression of 35 genes was highly up-regulated, this study lays the basis for further studies associated with NACs abiotic stress tolerance and adaptation in O. abyssinica and related plants.