Binding proteins for immunosuppressant drugs have been discovered recently in connection with the oligomeric structures of cytoplasmic steroid receptors. The binding proteins form complexes with known immunosuppressant drugs, such as rapamycin, FK5O6 and cyclosporin A and because there are elevations and declines in the functioning of the immune system with aging and other conditions, it seems likely that there exist one or more endogenous immunosuppressant agents whose levels may be under various types of control. In studying the reassembly of the glucocorticoid receptor non-DNA-binding complex form with purified proteins, we discovered a new protein complexed with the FKBP-52 (p55-59) immunophilin. Because this new protein is purified with the FKBP-52 from different cell lines and it appears only when FKBP-52 appears, we conclude that it may function in the signal transduction pathway of immunosuppressant action. Consequently, we plan to pursue the following objectives: (1) Full-length, truncated and mutated FKBP-52 will be overexpressed in the baculovirus system. Site directed mutagenesis will be followed by overexpression of the mutant proteins and all of these proteins will be purified. (2) Overexpressed and purified FKBP-52, hsp90, hsp7O and other cytosolic factors will be reconstituted into high molecular weight complexes, comparable to cellular complexes, and the effects of immunosuppressant drug ligands on these complexes will be assessed. (3) The 59kDa FKBP-52-associated new phosphoprotein will be cloned, overexpressed, purified and characterized. (4) The sequences in FKBP-52 that are responsible for binding to hsp9O, hsp7O, ATP and the 59kDa FKBP-52-associated protein will be determined by mutation of the FKBP-52 cDNA, overexpression of the derivative protein and assembly into the high molecular weight complex. (5) Specific antibodies against FKBP- 52 and its associated phosphoprotein will be developed. These experiments will clarify the signal transduction process involved in the pathway of drug-induced immunosuppression and may contribute to the methods required to discover the endogenous immunosuppressants, results that will directly affect organ and tissue transplantation.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
1R01AI035035-01
Application #
2070386
Study Section
Biochemistry Study Section (BIO)
Project Start
1994-01-01
Project End
1998-12-31
Budget Start
1994-01-01
Budget End
1994-12-31
Support Year
1
Fiscal Year
1994
Total Cost
Indirect Cost
Name
Thomas Jefferson University
Department
Pharmacology
Type
Schools of Medicine
DUNS #
061197161
City
Philadelphia
State
PA
Country
United States
Zip Code
19107
Steplewski, A; Ebel, W; Planey, S L et al. (2000) Phosphorylation of the insect immunophilin FKBP46 by the Spodoptera frugiperda homolog of casein kinase II. Gene 246:169-78
Song, Q; Alnemri, E S; Litwack, G et al. (1997) An immunophilin is a component of the insect ecdysone receptor (EcR) complex. Insect Biochem Mol Biol 27:973-82
Ahmad, M; Srinivasula, S M; Wang, L et al. (1997) Spodoptera frugiperda caspase-1, a novel insect death protease that cleaves the nuclear immunophilin FKBP46, is the target of the baculovirus antiapoptotic protein p35. J Biol Chem 272:1421-4
Robertson, N M; Zangrilli, J; Fernandes-Alnemri, T et al. (1997) Baculovirus P35 inhibits the glucocorticoid-mediated pathway of cell death. Cancer Res 57:43-7
Ahmad, M; Srinivasula, S M; Wang, L et al. (1997) CRADD, a novel human apoptotic adaptor molecule for caspase-2, and FasL/tumor necrosis factor receptor-interacting protein RIP. Cancer Res 57:615-9
Srinivasula, S M; Ahmad, M; Fernandes-Alnemri, T et al. (1996) Molecular ordering of the Fas-apoptotic pathway: the Fas/APO-1 protease Mch5 is a CrmA-inhibitable protease that activates multiple Ced-3/ICE-like cysteine proteases. Proc Natl Acad Sci U S A 93:14486-91
Bullrich, F; Fernandes-Alnemri, T; Litwack, G et al. (1996) Chromosomal mapping of cell death proteases CPP32, MCH2, and MCH3. Genomics 36:362-5
Fernandes-Alnemri, T; Armstrong, R C; Krebs, J et al. (1996) In vitro activation of CPP32 and Mch3 by Mch4, a novel human apoptotic cysteine protease containing two FADD-like domains. Proc Natl Acad Sci U S A 93:7464-9
Srinivasula, S M; Fernandes-Alnemri, T; Zangrilli, J et al. (1996) The Ced-3/interleukin 1beta converting enzyme-like homolog Mch6 and the lamin-cleaving enzyme Mch2alpha are substrates for the apoptotic mediator CPP32. J Biol Chem 271:27099-106
Fernandes-Alnemri, T; Litwack, G; Alnemri, E S (1995) Mch2, a new member of the apoptotic Ced-3/Ice cysteine protease gene family. Cancer Res 55:2737-42

Showing the most recent 10 out of 14 publications