Genome-wide characterization of soybean lysophosphatidic acid acyltransferases and functional characterization of the role of GmLPAT11 in salt stress

Lysophosphatidic acid acyltransferase (LPAT) enzymes are widely expressed in various plant species, and they contribute to growth, development, and stress responses. Currently, information regarding the LPAT gene family in soybeans is limited. In this study, genome-wide analyses identified 15 soybean LPATs, which were then evaluated for their conserved protein motifs. These genes were grouped into three clusters based on their phylogenetic relationships. Confocal microscopy was used to visualize the localization of six GmLPATs within Arabidopsis mesophyll protoplasts. cis-Acting regulatory element analyses and qRT-PCR experiments revealed that these GmLPATs were upregulated in response to hormonal stimulation or exposure to abiotic stressors, including drought, alkaline conditions, and salt stress. The expression patterns of these GmLPATs varied among different soybean tissue types. One member of the solLPAT1 subtype (GmLPAT11) was found to be upregulated in response to a range of treatments, highlighting its role in soybean salt stress responses. GmLPAT11 expression in Escherichia coli confirmed the LPAT activity of this recombinant enzyme, and overexpressing this LPAT reduced reactive oxygen species production in transgenic soybean plants, thereby enhancing their salt stress tolerance. Gene association analyses indicated that GmLPAT11 variants are closely associated with seedling salt tolerance, and a polymorphism in the GmLPAT11 CDS region was potentially associated with salt tolerance. These results provide new insights into the nature of the LPAT gene family in soybeans while also identifying promising candidate genes for future research efforts to enhance the overall salt tolerance of soybean crops.