Functional Plant Biology Functional Plant Biology Society
Plant function and evolutionary biology

Just Accepted

This article has been peer reviewed and accepted for publication. It is in production and has not been edited, so may differ from the final published form.

The LmSAP gene isolated from the halotolerant Lobularia maritima improves salt and ionic tolerance in transgenic tobacco lines

Rania Ben Saad , Ameny Khemekhem , Nihed Ben Halima , Karim Ben Hamed , Faical Brini , Walid SAIBI

Abstract

The A20/AN1 zinc-finger domain-containing proteins of the Stress Associated Proteins (SAPs) family are fast emerging as potential candidates for biotechnological approaches to improve abiotic stress tolerance in plants. We identified LmSAP, one of the SAPs genes in Lobularia maritima, a halophyte brassicaceae, through its transcript accumulation in response to salinity and ionic stresses. Sequence homology analysis revealed that LmSAP contains two conserved zinc-finger domains A20 and AN1. Phylogeny analyses showed that LmSAP exhibited high amino acid sequence identity to other plant SAPs. Heterologous expression of LmSAP in yeast increased cell tolerance to salt and osmotic stress. In addition, the overexpression of LmSAP conferred high salt and ionic tolerance to transgenic tobacco plants. Transgenic tobacco seedlings showed higher survival rates and antioxidant activities under salt and ionic stresses. Enhanced antioxidant activities paralleled lower malondialdehyde and superoxide anion O2− levels in the LmSAP transgenic seedlings. Overall, our results suggest that overexpression of LmSAP enhanced salt tolerance by maintaining ionic balance and limiting oxidative and osmotic stresses.

FP17202  Accepted 29 September 2017

© CSIRO 2017