Functional characterization of Medicago truncatula GRAS7, a member of the GRAS family transcription factors, in response to abiotic stress

Abstract

Transcriptional factors play an essential role in the regulation of developmental processes in plants. GRAS family transcription factors are plant specific, and GRAS members possess multiple functions involved in plant growth and in response to abiotic and biotic stress. The members are divided into several subgroups. This study is focused on one particular member, MtGRAS7, which belongs to the PAT subgroup. Based on constructed stable transgenic plants with a gain and loss of function of MtGRAS7, the phenotype of transgenic plants was described compared to control wild-type Medicago trucatula. The involvement of the gene in the response to abiotic stress – drought (350 mmol/L mannitol), salinity (150 mmol/L NaCl) and cold (temperature of 4 °C), was analyzed and its transcript level was detected in leaves and nodules at different time points during the exposure to stress and after the stress. The overexpression of the gene benefits plant during the stress and later on in the recovery period.