FKBP

FKBP (FK506 binding protein) is a family of proteins that are known for their ability to bind to the immunosuppressive drugs FK506 (tacrolimus) and rapamycin. They are found in a wide range of organisms, from bacteria to humans, and play a variety of roles in cellular processes.

Function

FKBPs are part of the larger family of immunophilins, which also includes the cyclophilins. They are characterized by their ability to bind to immunosuppressive drugs, but they also have other functions. For example, they are involved in protein folding, signal transduction, and the regulation of apoptosis.

FKBPs have a conserved domain, known as the FKBP-type peptidyl-prolyl cis-trans isomerase domain. This domain allows them to catalyze the interconversion of the cis and trans isomers of proline residues in proteins, which is a critical step in protein folding.

Clinical significance

FKBPs are the target of several immunosuppressive drugs, including FK506 and rapamycin. These drugs bind to the FKBP protein and then inhibit the activity of a protein called calcineurin, which is involved in the activation of T cells. This makes them useful in preventing organ rejection after transplantation.

In addition, mutations in FKBP genes have been associated with several diseases. For example, mutations in the FKBP10 gene can cause a form of osteogenesis imperfecta, a disorder that affects the bones.

See also

• Immunophilin
• Protein folding
• Signal transduction
• Apoptosis
• Osteogenesis imperfecta