Immunophilins in animals and higher plants

Immunophilins were originally discovered as receptors for a family of immunosuppressive drugs including cyclosporin, FK506, and rapamycin. These drugs suppress immune reaction and are clinically used to prevent graft rejection during organ transplantation. More recently, immunophilins have been found in all eukaryotes ranging from yeast, animals, and higher plants, implicating these proteins in foundamental cellular processes. Biochemical analyses have shown that all immunophilins studied so far possess an enzyme activity involved in protein folding. However, a number of more specific functions for immunophilins have also been discovered in mammalian systems. Although research on plant immunophilins is more primitive, ongoing studies suggest that these proteins may play unique roles in plant growth and development. This article will briefly summarize research activities on both animal and plant immunophilins, a promising new area of current biology.