Identification of Gene Family in and Its Function Analysis under Stress.

Tomato is an important vegetable crop. In the process of tomato production, it will encounter abiotic stress, such as low temperature, drought, and high salt, and biotic stress, such as pathogen infection, which will seriously affect the yield of tomato. Calcium-dependent protein kinase (CDPK) is a class of major calcium signal receptor which has an important regulatory effect on the perception and decoding of calcium signals. CDPK plays a key role in many aspects of plant growth, such as the elongation of pollen tubes, plant growth, and response to biotic and abiotic stress. While some studies have concentrated on and pepper, is a wild species relative of cultivated tomato and there is no report on CDPK in to date. Using tomato genomic data, this study identified 33 members of the gene family. Evolutionary analysis divides family members into four Asian groups, of which the CDPK family members have 11 gene replication pairs. Subcellular location analysis showed that most proteins were predicted to be located in the cytoplasm, and less protein existed on the cell membrane. Not all CDPK family members have a transmembrane domain. Cis regulatory elements relating to light, hormones, and drought stress are overrepresented in the promoter region of the genes in . The expression levels of each gene under biotic stress and abiotic stress were quantified by qRT-PCR. The results showed that members of the CDPK family in respond to different biotic and abiotic stresses. Among them, the expression of and genes change significantly. and genes were silenced using VIGS (virus-induced gene silencing), and the silenced plants illustrated reduced stress resistance to cold, and drought stress. The results of this study will provide a basis for the in-depth study of the gene family in , laying the foundation for further analysis of the function of the gene family.