Genome-Wide Analysis and Cloning of the Tea (<i>Camellia-sinensis</i>) Encoding FK506-Binding Proteins (FKBPs) Reveals <i>CsFKBP53</i>, Which Confers Tolerance to Low Temperature Stresses in Transgenic <i>Arabidopsis</i>

FK506-binding proteins (FKBPs) belong to the peptidyl-prolyl cis/trans isomerase (PPIase) Super-family and are involved in a wide range of biological processes including protein folding, hormone signalling, plant growth and stress responses. However, the FKBPs and their biological functions have not been identified in tea. In this study, we searched and identified 21 FKBP genes in the tea plant genome using the consensus model of the FK506 binding domain (PF00254). Their phylogeny, classification, structure, motifs, interactors and expression patterns were analysed. Comprehensive qRT-PCR analysis revealed different expression patterns of CsFKBPs in different tissues and in response to low-temperature. We performed a genome-wide analysis of the low-temperature expression pattern of this gene family and determined that overexpression of CsFKBP53 enhances low-temperature tolerance in Arabidopsis plants. Furthermore, the expression of CsFKBP53 differed significantly in different tea varieties. Our results suggest that the FKBP gene is highly conserved in plant species and that transgenic CsFKBP53 can improve low temperature resistance in plants.