Genome-Wide Identification and Expression Analysis of the TCP Genes in Jatropha curcas L. Reveals Its Roles in Involvement of Leaf Shape

Jatropha curcas var. nigroviensrugosus CV Yang (Jn) exhibits wrinkled leaves and higher flowering and fruiting rates compared to Jatropha curcas L. (Jc). Teosinte branched1/Cincinnata/Proliferating cell factors (TCPs) are known to play crucial roles in plant development and physiological processes. However, it remains unknown whether or not the TCP gene family regulates in leaf development of Jc and Jn. Here, we systematically performed a genome-wide analysis of the Jc TCP family and investigated the differences in the expression of TCP in different leaf morphologies. In total, our results showed that 18 TCP members were identified in the whole genome sequence of Jatropha curcas L.; Jc TCP genes were classified into two categories by phylogenetic tree construction, among which there were 11 members in the Class I subfamily, seven members in the Class Ⅱ subfamily. It was shown that 12 members of Jc TCP genes were located at the seven chromosomes, and proteins belonging to the same TCP group exhibit higher similarity than those from different groups. Furthermore, the expression profiles of 15 TCP genes were discovered at different leaf developmental stages of Jc and Jn. Jc TCP 4, Jc TCP 5, Jc TCP 8, Jc TCP 13, Jc TCP 14, and Jc TCP 16 showed significantly different expressions, and can be used as candidate genes for regulating leaf development. Therefore, the TCP genes play important roles in regulating the leaf development in Jc, and the manipulation of Jc TCP genes can potentially be an important tool used for the genetic improvement of the leaf.