Cell proliferation through forced engagement of c-Kit and Flt-3.
To investigate the potential for functional interactions between heterologous receptors, the cytoplasmic domains of 2 different receptors (c-Kit and Flt-3) were coexpressed in the interleukin-3-dependent cell line Ba/F3. The receptor signaling domains were presented in the context of fusion proteins, with c-Kit linked to the FK506 binding protein (FKBP12) and Flt-3 linked to the FRB domain of the FKBP12-rapamycin-associated protein. The fusions were brought into apposition with the use of chemical inducers of dimerization (CIDs). Two classes of CID were employed. FK1012 and its synthetic analogue AP1510 bring together 2 copies of the FKBP12 domain, thereby inducing homodimerization of the c-Kit(FKBP12) fusion. A second type of CID, rapamycin, brings together one FKBP12 domain and one FRB domain, resulting in heterodimerization of the c-Kit(FKBP12) and Flt-3(FRB) fusions. Ba/F3 cell growth was promoted not only by FK1012- or AP1510-induced homodimerization of the c-Kit(FKBP12) fusion (as reported previously), but also by rapamycin-induced c-Kit(FKBP12)-Flt-3(FRB) heterodimerization. These findings demonstrate the potential for a direct functional interaction between c-Kit and Flt-3. (Blood. 2001;97:3662-3664)
Otto
K G
KG
Division of Hematology, Department of Medicine, University of Washington, Seattle, WA 98195, USA.
Jin
L
L
Spencer
D M
DM
Blau
C A
CA
D000818:Animals; D001665:Binding Sites; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D019281:Dimerization; D004347:Drug Interactions; D015870:Gene Expression; D007377:Interleukin-3 / Q000494:pharmacology; D051379:Mice; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000502:physiology*; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000502:physiology*; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000502:physiology*; D011993:Recombinant Fusion Proteins; D015398:Signal Transduction; D020123:Sirolimus / Q000378:metabolism; D016559:Tacrolimus / Q000031:analogs & derivatives / Q000494:pharmacology; D022021:Tacrolimus Binding Proteins / Q000378:metabolism; D051941:fms-Like Tyrosine Kinase 3
C119717:AP 1510; C084260:FK 1012; D007377:Interleukin-3; D011518:Proto-Oncogene Proteins; D011993:Recombinant Fusion Proteins; C497971:Flt3 protein, mouse; D019009:Proto-Oncogene Proteins c-kit; D020794:Receptor Protein-Tyrosine Kinases; D051941:fms-Like Tyrosine Kinase 3; D022021:Tacrolimus Binding Proteins; D020123:Sirolimus; D016559:Tacrolimus