Small secreted peptides (SSPs) in tomato and their potential roles in drought stress response

Abstract

Tomato (Solanum lycopersicum) is one of the most important vegetable crops in the world and abiotic stresses often cause serious problems in tomato production. It is thus important to identify new regulators in stress response and to devise new approaches to promote stress tolerance in tomato. Previous studies have shown that small secreted peptides (SSPs) are important signal molecules regulating plant growth and stress response by mediating intercellular communication. However, little is known about tomato SSPs, especially their roles in responding to abiotic stresses. Here we report the identification of 1,050 putative SSPs in the tomato genome, 557 of which were classified into 38 known SSP families based on their conserved domains. GO and transcriptome analyses revealed that a large proportion of SlSSPs might be involved in abiotic stress response. Further analysis indicated that stress response related cis-elements were present on the SlCEP promotors and a number of SlCEPs were significantly upregulated by drought treatments. Among the drought-inducible SlCEPs, SlCEP10 and SlCEP11b were selected for further analysis via exogenous application of synthetic peptides. The results showed that treatments with both SlCEP10 and SlCEP11b peptides enhanced tomato drought stress tolerance, indicating the potential roles of SlSSPs in abiotic stress response. Graphical Abstract

Research Progress of Small Plant Peptides on the Regulation of Plant Growth, Development, and Abiotic Stress

“…When plants experience salt stress, exacerbating cell damage leads to the release of AtPEP3, which in turn induces downstream signaling responses. However, the intricacies Research on CEP regulation of plant drought tolerance has been extensive, and studies in crops such as wheat and tomato have revealed the crucial role of CEP in enhancing plant drought tolerance [80]. Application of the TaCEP1D peptide on wheat leaves has been shown to improve drought resistance [81].…”

Identification and Application of CLE Peptides for Drought Resistance in Solanaceae Crops

“…28 In tomatoes, treatments with the drought-induced SlCEPs (Solanum lycopersicum C-terminally encoded peptides), specifically SlCEP10 and SlCEP11b peptides, have been found to enhance drought resistance. 29 Moreover, sbt3.8 (subtilisin-like serine proteases 3.8) mutants exhibit compromised tolerance to drought and osmotic stress, which can be ameliorated with PSK (Phytosulfokine) peptide treatment. 30 In this study, we discovered that two CLE peptides, NtCLE2 and NtCLE3, from a Nicotiana tabacum can trigger stomatal closure in three solanaceous plants (Nicotiana tabacum, Capsicum annuum, and Solanum melongena).…”

“…Compared to the wild type, rice plants overexpressing OsDT11 ( drought tolerance 11 , which encodes a novel cysteine-rich peptide) exhibited significant reductions in water loss and stomatal density, while the concentration of ABA increased substantially . In tomatoes, treatments with the drought-induced SlCEPs (Solanum lycopersicum C-terminally encoded peptides), specifically SlCEP10 and SlCEP11b peptides, have been found to enhance drought resistance . Moreover, sbt3.8 ( subtilisin-like serine proteases 3.8 ) mutants exhibit compromised tolerance to drought and osmotic stress, which can be ameliorated with PSK (Phytosulfokine) peptide treatment …”

Comparative Genomics Screens Identify a Novel Small Secretory Peptide, SlSolP12, which Activates Both Local and Systemic Immune Response in Tomatoes and Exhibits Broad-Spectrum Activity

“…26 Therefore, a standardized pipeline has been established for screening potential SSPs for certain species, as has been applied in Arabidopsis thaliana and tomato plants. 3,27 Solanaceae is one of the most important plant families in horticulture, encompassing a multitude of vital crops and ornamental plants such as tobacco (Nicotiana tabacum), pepper (Capsicum annuum), and tomato (Solanum lycopersicum). 28 The first small peptide discovered in tomato plants, known as Sys, mediates long-distance immune responses through its receptor, systemin receptor 1 (SYR1).…”