Evidence for the ligand-induced conversion from a dimer to a tetramer of the granulocyte colony-stimulating factor receptor.
FEBS Lett
; 356(2-3): 255-60, 1994 Dec 19.
Article
en En
| MEDLINE
| ID: mdl-7805849
ABSTRACT
An extracellular portion of granulocyte colony-stimulating factor (G-CSF) receptor, which contains an immunoglobulin-like (Ig) domain and cytokine receptor homologous (CRH) region, was secreted into the medium using Trichoplusia ni-Autographa californica nuclear polyhedrosis virus system. The gene product was purified to homogeneity mainly as a dimer (85 kDa) using G-CSF affinity column chromatography and gel filtration HPLC, although the product existed as a monomer (45 kDa) in the medium. Scatchard analyses suggested that only the dimer had high affinity ligand binding (Kd = about 100 pM), which is comparable with the Kd value of the cell surface receptor. The binding of G-CSF to Ig-CRH induced its tetramerization (200-250 kDa). The molecular composition of the tetrameric complex showed a stoichiometry of four ligands bound to four Ig-CRH. These results suggested that the oligomeric mechanism of the G-CSF receptor differs from that reported for growth hormone (GH) receptor, although CD spectrum spectroscopy suggested that the Ig-CRH has a GH receptor-like structure.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Receptores de Factor Estimulante de Colonias de Granulocito
Límite:
Animals
Idioma:
En
Revista:
FEBS Lett
Año:
1994
Tipo del documento:
Article
País de afiliación:
Japón