Structure and biological functions of plant FKBP family

: FK506-binding proteins (FKBPs) are well known as both the receptor for the immunosuppressant drug FK506 and the prolyl isomerase (PPIase) enzyme. FKBPs are widely and constitutively expressed, and highly conserved during evolution. In higher plants, FKBPs usually form a relative large and diverse family compared with that in other eukaryotes, and serve as important molecular chaperones that interact with specific protein partners to regulate a diversity of cellular processes which mainly influence the plant development and stress responding. More recently, studies discovered a series of new interacting partners of FKBPs, which implicate FKBPs in gene expression regulation and photosynthetic adaptation. This review mainly focuses on the structural characteristics, classification, and the latest discoveries in the physiological functions of FKBPs in higher plants.