Identification of Tomato C2 Gene Family and Functional Analysis of the Inflorescence Branching Regulatory Gene SlC2–25

The C2 domain plays an important role in plant growth and development. We performed genome-wide identification of SlC2 gene family members by bioinformatics, and predictive analysis of chromosome distribution, evolutionary relationships, gene structure and colinearity of their family members. The results showed that a total of 103 SlC2 genes were screened, according to the order of their physical coordinates, 103 SlC2 genes were named from SlC2-1 to SlC2-103. The amino acid lengths ranged from 107 to 2133aa, the molecular weights ranged from 12,416.96 to 229,427.7 Da, and the isoelectric points ranged from 4.18 to 9.94. The cluster analysis was divided into six subgroups, and the gene sequences were highly conserved. Based on the pre-laboratory transcriptome data, we screened the SlC2-25 gene, analyzed the expression pattern of SlC2-25 in two kinds of tomato inflorescences by RT-qPCR, and preliminarily explored the function of SlC2-25 in the regulation of tomato inflorescence meristem by using gene editing technology, and found that SlC2-25 was a negative regulator of tomato inflorescence branching. In addition, the endogenous hormone content of tomato inflorescences was determined, and it was hypothesized that the SlC2s genes might be involved in the regulatory process of tomato inflorescence branching by altering the content of endogenous hormones in the plant or by interacting with a variety of proteins.