Chickpea R2R3 Transcription Factor CaMYB78 Enhances Abiotic Stress Tolerance in Tobacco

MYB transcription factors constitute one of the most prominent Transcription Factors gene families, which play a significant role in plants' abiotic and biotic stress responses. A novel stress-responsive R2R3 MYB TF gene known as CaMYB78 was isolated from chickpea. The expression of CaMYB78 was upregulated in response to NaCl, Mannitol, and ABA treatments in chickpea. CaMYB78 was found to be localized in the nucleus. Heterologous expression of CaMYB78 in Nicotiana tabacum plants showed increased antioxidation activities in terms of increased enzyme activity, gene expression, and increased content of Osmo protectants. Transgenic lines also exhibited higher RWC, lower water loss in drought stress, and lower Na+ concentration in salt stress. In addition, several antioxidant genes and stress-related genes were also found to be upregulated in transgenic lines upon salt and drought stress, thus indicating better stress tolerance capacity of transgenic plants. The functional characterization of chickpea MYB78 demonstrates that it plays a crucial part in abiotic stress response in plants, thus providing a scientific basis for future research in stress biology.