Meta-analysis of the effect of expression of MYB transcription factor genes on abiotic stress.

Background: MYB proteins are a large group of transcription factors. The overexpression of MYB genes has been reported to improve abiotic stress tolerance in plant. However, due to the variety of plant species studied and the types of gene donors/recipients, along with different experimental conditions, it is difficult to interpret the roles of MYB in abiotic stress tolerance from published data.

Methods: Using meta-analysis approach, we investigated the plant characteristics involved in cold, drought, and salt stress in MYB-overexpressing plants and analyzed the degrees of influence on plant performance by experimental variables.

Results: The results show that two of the four measured plant parameters in cold-stressed plants, two of the six in drought-stressed, and four of the 13 in salt-stressed were significantly impacted by MYB overexpression by 22% or more, and the treatment medium, donor/recipient species, and donor type significantly influence the effects of MYB-overexpression on drought stress tolerance. Also, the donor/recipient species, donor type, and stress duration all significantly affected the extent of MYB-mediated salt stress tolerance. In summary, this study compiles and analyzes the data across studies to help us understand the complex interactions that dictate the efficacy of heterologous MYB expression designed for improved abiotic stress tolerance in plants.