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Serine hydroxymethyltransferase (SHMT) is one of the most important enzyme families in one-carbon metabolic pathway and photorespiration within plant cells. Recently studies reported the active roles of plant SHMTs in defending abiotic stresses. However, genome-scale analysis of SHMT in tomato is currently unknown. In this study, seven SHMT genes were identified in the tomato genome using a genome-wide search approach. In addition, their physicochemical properties, protein secondary structure, subcellular localization, gene structure, conserved motifs, phylogenetic and collinear relationships were analyzed. Our results demonstrated that tomato SHMT members were divided into two group and four subgroups, and they were conserved with the orthologs of other plants. Analysis of cis-acting elements showed that each of the SlSHMT genes contained different kinds of hormones and stress-related cis-acting elements in their promoter regions. Finally, qRT-PCR analysis indicated that SlSHMTs were expressed at different levels in different tissues, and they responded to UV, cold, heat, NaCl, H2O2, ABA and PEG treatments. These results provided definite evidence that SlSHMTs might involve in growth, development and stress responses in tomato, which laid a foundation for future functional studies of SlSHMTs.

Hydrogen sulfide (H2S) is known to have a positive effect on the postharvest storage of vegetables and fruits, but limited results are available on its influence in fruit flavor quality. Here, we presented the effect of H2S on the flavor quality of tomato fruit during postharvest. H2S decreased the content of fructose, glucose, carotene and lycopene but increased that of soluble protein, organic acid, malic acid and citric acid. These differences were directly associated with the expression of their metabolism-related genes. Moreover, H2S treatment raised the contents of total phenolics, total flavonoids and most phenolic compounds, and up-regulated the expression level of their metabolism-related genes (PAL5, 4CL, CHS1, CHS2, F3H and FLS). However, the effects of the H2S scavenger hypotaurine on the above flavor quality parameters were opposite to that of H2S, thus confirming the role of H2S in tomato flavor quality. Thus, these results provide insight into the significant roles of H2S in tomato fruit quality regulation and implicate the potential application of H2S in reducing the flavor loss of tomato fruit during postharvest.

The calmodulin-binding transcription activator (CAMTA), as one of the most distinctive families of transcription factors, plays an important role in plant growth and development and in the stress response. However, it is currently unknown whether CAMTA exists in cucumbers and what its function is. In this study, we first identified four CAMTA genes in the cucumber genome using a genome-wide search method. Subsequently, we analyzed their physical and chemical properties, gene structure, protein domains, and phylogenetic relationships. The results show that the structure of CsCAMTAs is similar to that of other plants, and a phylogenetic analysis divides them into three groups. The analysis of cis-acting elements shows that most CsCAMTAs contain a variety of hormones and stress-related elements. The RT-PCR analysis shows that CsCAMTAs have different expression levels in different tissues and can be induced by IAA, ABA, MeJA, NaCl, and PEG. Finally, we analyzed the expression pattern of CsCAMTAs’ alternative spliceosomes under salt and drought stress. The results show that the expression levels of the different spliceosomes are affected by the type of stress and the duration of stress. These data indicate that CsCAMTAs participate in growth and development and in the stress response in cucumbers, a finding which lays the foundation for future CsCAMTAs’ functional research.