NMR resonance assignments of the FKBP domain of human aryl hydrocarbon receptor-interacting protein-like 1 (AIPL1) in complex with a farnesyl ligand

Aryl hydrocarbon receptor-interacting protein-like 1 (AIPL1) is a specialized chaperone of phosphodiesterase 6, a key effector enzyme in the phototransduction cascade. The FKBP domain of AIPL1 is known to bind the farnesyl moiety of PDE6. Mutations in AIPL1, including many missense mutations in the FKBP domain, have been associated with Leber congenital amaurosis, a severe blinding disease. Here, we report the backbone and sidechain assignments of the N-terminal FKBP Delta loop (with a loop deletion) of AIPL1 in complex with a farnesyl ligand. We also compare the predicted secondary structures of FKBP Delta loop with those of a highly homologous AIP FKBP. These results show that the FKBP domains of AIP and AIPL1 have similar folds, but display subtle differences in structure and dynamics. Therefore, these assignments provide a framework for further elucidation of the mechanism of farnesyl binding and the function of AIPL1 FKBP.