Identification of the GPATs gene family in tomato and expression analysis under low temperature stress

Objective To identify tomato GPATs gene family members and analyze gene expression patterns in order to provide a basis for functional studies of individual members of the tomato GPATs gene family.

Methods Fifteen SlGPAT members were identified in tomato by bioinformatic analysis, and analyses of physicochemical properties, gene structure, phylogeny, covariance, and cis-acting elements were carried out, as well as analysis of the expression pattern of the SlGPAT genes in response to low-temperature stress using qPCR.

Results Tomato SlGPAT was unevenly distributed on 10 chromosomes, and most of them were localized in plastids and were basic proteins. Phylogenetic relationships revealed that tomato GPATs could be classified into three clusters, and genes with the same conserved structural domains had similar gene structures; collinearity analysis revealed that there was gene duplication in the SlGPAT gene family, suggesting that the GPAT gene may have amplified family members through duplication during the evolutionary process; analysis of cis-acting elements revealed that the SlGPATs gene contains cis-acting elements associated with photoreactions, plant hormones, and abiotic stress. The qPCR analysis revealed that half of the SlGPAT genes were up-regulated under low-temperature stress, and the expression of SlGPAT12 reached the maximum at 24 h, which was 32 times higher than that at 0 h.

Conclusion This study provides insights into the functional roles of tomato GPAT genes and identifies important candidate genes for genetic improvement of fatty acid metabolism in tomatoes.