Trehalose-6-phosphate synthase gene expression analysis under abiotic and biotic stresses in bottle gourd (Lagenaria siceraria)

Trehalose (Tre) is a non-disaccharide that regulates environmental stress tolerance in animals and plants, and is synthesized by Trehalose-6-phosphate synthase (TPS). This study aimed to analyze TPS genes in bottle gourd as this species has not been investigated before despite its economic importance and health benefits. Six TPS genes in Lagenaria siceraria (LsTPS) were identified and found to be distributed across six chromosomes. The LsTPS genes were categorized into Classes I and II based on their homology with Arabidopsis, rice, cucumber, watermelon, and tomato. Variable exon numbers were found in the LsTPS genes, with more exons in Class II than in Class I genes. GO term enrichment and cis-regulatory element analyses indicated that LsTPS genes participate in Tre synthesis and environmental stress responses. Structural analysis of TPS proteins revealed that LsTPS5 has a transmembrane helix, an α-helix and β-sheet. Gene duplication analysis indicated that purifying selection drove the evolution of the LsTPS family. We found that LsTPS genes are widely expressed in all plant tissues, and LsTPS1/5 are constitutively expressed in all tissues. RNA-sequencing and quantitative real-time PCR data showed that LsTPS expression changed significantly in response to environmental stressors. This study provides to foundation for further research on the roles of the LsTPS gene and Tre in abiotic and biotic stress response and provides important insights for the development of genetic engineering methods to alter Tre metabolism and interactions with other molecules.