FKBP12 dimerization mutations effect FK506 binding and differentially alter calcineurin inhibition in the human pathogen Aspergillus fumigatus.

Juvvadi, Praveen R

Bobay, Benjamin G

Gobeil, Sophie MC

Cole, D Christopher

Venters, Ronald A

Heitman, Joseph

Spicer, Leonard D

Steinbach, William J

2023-09-01T13:31:04Z

2023-09-01T13:31:04Z

2020-05

2023-09-01T13:31:03Z

The 12-kDa FK506-binding protein (FKBP12) is the target of the commonly used immunosuppressive drug FK506. The FKBP12-FK506 complex binds to calcineurin and inhibits its activity, leading to immunosuppression and preventing organ transplant rejection. Our recent characterization of crystal structures of FKBP12 proteins in pathogenic fungi revealed the involvement of the 80's loop residue (Pro90) in the active site pocket in self-substrate interaction providing novel evidence on FKBP12 dimerization in vivo. The 40's loop residues have also been shown to be involved in reversible dimerization of FKBP12 in the mammalian and yeast systems. To understand how FKBP12 dimerization affects FK506 binding and influences calcineurin function, we generated Aspergillus fumigatus FKBP12 mutations in the 40's and 50's loop (F37 M/L; W60V). Interestingly, the mutants exhibited variable FK506 susceptibility in vivo indicating differing dimer strengths. In comparison to the 80's loop P90G and V91C mutants, the F37 M/L and W60V mutants exhibited greater FK506 resistance, with the F37M mutation showing complete loss in calcineurin binding in vivo. Molecular dynamics and pulling simulations for each dimeric FKBP12 protein revealed a two-fold increase in dimer strength and significantly higher number of contacts for the F37M, F37L, and W60V mutations, further confirming their varying degree of impact on FK506 binding and calcineurin inhibition in vivo.

S0006-291X(20)30547-7

0006-291X

1090-2104

https://hdl.handle.net/10161/28891

eng

Elsevier BV

Biochemical and biophysical research communications

10.1016/j.bbrc.2020.03.062

Humans

Aspergillus fumigatus

Tacrolimus

Calcineurin

Tacrolimus Binding Protein 1A

Fungal Proteins

Amino Acid Sequence

Protein Structure, Secondary

Protein Binding

Mutation

Computer Simulation

Mutant Proteins

Protein Multimerization

Calcineurin Inhibitors

FKBP12 dimerization mutations effect FK506 binding and differentially alter calcineurin inhibition in the human pathogen Aspergillus fumigatus.

Journal article

Bobay, Benjamin G|0000-0003-4775-3686

Venters, Ronald A|0000-0001-6457-823X

Heitman, Joseph|0000-0001-6369-5995

Spicer, Leonard D|0000-0001-5655-0093|0000-0003-2911-6130

48

54

1

Duke

School of Medicine

Faculty

Basic Science Departments

Clinical Science Departments

Institutes and Centers

Cell Biology

Molecular Genetics and Microbiology

Pharmacology & Cancer Biology

Medicine

Radiology

Medicine, Infectious Diseases

Duke Cancer Institute

Duke Human Vaccine Institute

Published

526