Analysis of Gene Expression Pattern of Some Members of NAC Gene Family in Lentil (Lens Culinaris M.) Under Cold Stress

Cold is one of the important stresses in cold and temperate regions and improving cold tolerance is in the top priority of the lentil breeding programs. NAC transcription factors play an important role in response to various biological stresses, including cold stress. In this study, to evaluate the expression of MfNAC, MtNAC57 and GmNAC2 genes, the plants of Gachsaran lentil cultivar were subjected to five temprature treatments in a completely randomized design with three replications. Twenty-nine old plants were subjected to duration of cold stress treatments including 6h, 12h, 24h and 48h at 2°-4°c and plants grown under greenhouse conditions (23°C) were considered as controls. Total RNA extraction from tissues was performed using lithium chloride method and cDNA was synthesized using TaKara kit. For each treatment, real-time PCR was performed in both shoot and root in three biological and two technical replications. Actin gene was used as internal control. The results of analysis of variance of all studied genes showed that there was a significant difference between the different duration of cold treatments in both shoot and root. GmNAC2 gene expression decreased significantly in the shoot, 6 hours after stress, while in the root, the expression decreased 24 hours after stress. The expression of MtNAC57 gene in 6h, 12h, and 24h treatments decreased compared to control, but in the root in 12h treatment, a significant expression was observed. MfNAC gene in shoot showed a significant reduction in expression in all treatments, while in root a significant increase was only observed during long-term treatment of 48h. In the present study, for first time, the expression pattern of some members of NAC gene family was examined in lentils under cold stress and the results could be useful for studies on this plant and other legumes.