[Genome-wide identification and analysis of the TCP gene family in eggplant (Solanum melongena L.)]

TCP (teosinte branched1/cincinnata/proliferating cell factor) is a group of plant-specific transcription factors that play important roles in plant growth and development. To date, there are no report about TCP transcription factors in eggplant (Solanum melongena L). In this study, twenty-nine eggplant TCP (SmTCP) family genes distributed on 11 chromosomes were identified from the genome database of eggplant using bioinformatics methods. The results showed that all members of the family contained sequences encoding TCP conserved domains with length of amino acids ranging from 201 to 538 and exon numbers of 1 or 2. Subcellular localization revealed that three SmTCP proteins (SmTCP02/03/21) were located in the cytoplasm and the other SmTCP proteins were located in the nucleus. The 29 TCP transcription factors were divided into ClassⅠ (PCF) and ClassⅡ (CIN and CYC/TB1) by phylogenetic tree and sequence analysis. Collinearity analysis showed that 17 pairs (21) of SmTCP genes had collinearity, and these collinearity genes belonged to segmental duplication. Analysis of gene expression patterns showed that all 29 members of SmTCP gene family were expressed in 15 tissues or organs, but the expression patterns were different. Among them, four gene (SmTCP18/19/20/25) of CIN subfamily were highly expressed in leaves at different growth stages. Analysis of cis-acting elements in the promoter region of SmTCP showed that there were four types of cis-acting elements, which were light response related cis-acting elements, growth and development related cis-acting elements, hormone response related cis-acting elements and stress related cis-acting elements. In summary, the molecular basis of SmTCP genes in eggplant and the influence of TCP gene on the growth and development of eggplant provided a theoretical basis for molecular breeding of eggplant.