Overexpression of peanut (Arachis hypogaea L.) AhGRFi gene in Arabidopsis thaliana enhanced root growth inhibition under exogenous NAA treatment

Abstract

Abstract The 14-3-3 protein is a kind of evolutionary ubiquitous protein family highly conserved in eukaryotes. Initially, 14-3-3 proteins were reported in mammalian nervous tissues, but in the last decade, their role in various metabolic pathways in plants established the importance of 14-3-3 proteins. In present study, a total of 22 14-3-3 genes also called as general regulatory factors (GRF) were identified in the peanut (Arachis hypogaea) genome out of which 12 belonged to the ε group whereas 10 of them belonged to the non- ε-group. Tissue-specific expression of identified 14-3-3 genes was studied using transcriptome analysis. The peanut AhGRFi gene was cloned and transformed in Arabidopsis thaliana. The investigation of subcellular localization indicated that AhGRFi is localized in the cytoplasm. Overexpression of the AhGRFi gene in transgenic Arabidopsis shown that under exogenous 1-naphthaleneacetic acid (NAA) treatment, root growth of transgenic plants was inhibited when compared with control. NAA-responsive endogenous relative gene expressions in AhGRFi transgenic Arabidopsis were validated by real-time PCR. The AhGRFi may be involved in the auxin signaling during seedling root development. An in-depth study on the molecular mechanism of this process remains to be further explored.