Peptidyl-prolyl cis-trans isomerase FKBP1A (FKBP12) engineered domain (FKBP12 (engineered))

The engineered FKBP12 domain, most commonly featuring the F36V mutation, is a modified version of the human FK506-binding protein 1A (FKBP12) designed for precise pharmacological control of protein function (Nabet et al., 2018, Nature Chemical Biology). This specific mutation creates a sub-pocket that accommodates bumped synthetic ligands, such as dTAG-13 or rimiducid, which do not bind to the wild-type FKBP12 protein, thereby ensuring high selectivity and minimal off-target effects (Clackson et al., 1998, PNAS). When fused to a protein of interest (POI), the engineered FKBP12 domain acts as a degron or a dimerization handle. In the degradation TAG (dTAG) system, heterobifunctional small molecules (PROTACs) recruit E3 ubiquitin ligases like Cereblon (CRBN) or Von Hippel-Lindau (VHL) to the fusion protein, facilitating its rapid ubiquitination and subsequent proteasomal degradation (Winter et al., 2015, Science). This technology is widely utilized in drug discovery to validate therapeutic targets and in cell therapy as a safety switch (e.g., rimiducid-induced apoptosis in CAR-T cells) to manage adverse events like cytokine release syndrome (Di Stasi et al., 2011, NEJM). The engineered domain provides a versatile platform for studying protein-protein interactions and developing inducible therapeutic systems across various disease models, particularly in oncology and regenerative medicine.

Other names

FKBP12-F36VdTAG domainFKBP12 mutantFK506-binding protein 1A (engineered)FKBP12vFKBP12 (F36V)

Recruitment of E3 ubiquitin ligases (e.g., CRBN, VHL) for proteasomal degradation or chemically induced dimerization to trigger cellular signaling or apoptosis.