Systematic Annotation Reveals CEP Function in Tomato Root Development and Abiotic Stress Response

Tomato ( ) is one of the most important vegetable crops worldwide; however, environmental stressors severely restrict tomato growth and yield. Therefore, it is of great interest to discover novel regulators to improve tomato growth and environmental stress adaptions. Here, we applied a comprehensive bioinformatics approach to identify putative tomato ( ) genes and to explore their potential physiological function in tomato root development and abiotic stress responses. A total of 17 tomato genes were identified and grouped into two subgroups based on the similarity of CEP motifs. The public RNA-Seq data revealed that tomato genes displayed a diverse expression pattern in tomato tissues. Additionally, genes expression was differentially regulated by nitrate or ammonium status in roots and shoots, respectively. The differences in expression levels of genes induced by nitrogen indicate a potential involvement of s in tomato nitrogen acquisition. The synthetic CEP peptides promoted tomato primary root growth, which requires nitric oxide (NO) and calcium signaling. Furthermore, we also revealed that CEP peptides improved tomato root resistance to salinity. Overall, our work will contribute to provide novel genetic breeding strategies for tomato cultivation under adverse environments.