Abstract
Glycerol-3-phosphate acyltransferase is the first acyl esterifying enzyme in phosphatidylglycerol (PG) synthesis process. In this study, we isolated and characterized the glycerol-3-phosphate acyltransferase (GPAT) gene from Suaeda salsa (S. salsa) and obtained the full length of the GPAT gene from S. salsa (SsGPAT) by 5′ and 3′ RACE. The clone contained an open reading frame (ORF) of 1167 bp nucleotides that comprised of 388 amino acid residues. Real-time PCR revealed that the mRNA accumulation of GPAT in S. salsa was induced by salt stress. The highest expression levels were observed when S. salsa leaves were exposed to 300 mM NaCl treatment. At the germination stage, the germination rate and root length of overexpressed Arabidopsis strains were significantly higher than WT under different concentrations of NaCl treatments, while the inhibitory effect was significantly severe in T-DNA insertion mutant strains. In the seedling stage, chlorophyll content, the photochemical efficiency of PSII, PSI oxidoreductive activity (ΔI/Io), and the unsaturated fatty acid content of PG decreased less in overexpressed strains and more in mutant strains than that in WT under salt stress. These results suggest that the overexpression of SsGPAT in Arabidopsis enhances salt tolerance and alleviates the photoinhibition of PSII and PSI under salt stress by improving the unsaturated fatty acid content of PG.
Highlights
Salt stress is one of the main abiotic stresses
Our results revealed that glycerol-3-phosphate acyltransferase (GPAT) from euhalophyte S. salsa improved salt tolerance and alleviated the salt-induced photoinhibition of Photosystem II (PSII) and PSI by increasing the unsaturated fatty acid content of PG in Arabidopsis
The SsGPAT gene contained a complete open reading frame (ORF) of 1167 bp and the SsGPAT was comprised of 388 amino acids with a molecular mass of 43 kDa (Figure 1A)
Summary
Soil salinization is a worldwide problem (Zhu, 2001) and limits the production of various crops all over the world (Munns and Tester, 2008). How plants sense stress signals and adapt to adverse environments are fundamental biological questions (Zhu, 2016). Throughout evolution, plants have developed many mechanisms to adjust to salt stress, such as causing a series of physiological and biochemical changes, and inducing the expression of functional and regulatory genes. The mechanism of salt stress to plant survival and resistance is complex, and requires further exploration. Salt stress is known to inhibit photosynthesis through the process of photoinhibition. It is reported that Photosystem II (PSII) plays an important role in the process of leaf photosynthesis adapting to environmental perturbations (Baker, 1991).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
