CHARACTERIZATION OF HIGH-AFFINITY AND LOW-AFFINITY RECEPTORS FOR CILIARY NEUROTROPHIC FACTOR

Citation
J. Huber et al., CHARACTERIZATION OF HIGH-AFFINITY AND LOW-AFFINITY RECEPTORS FOR CILIARY NEUROTROPHIC FACTOR, European journal of biochemistry, 218(3), 1993, pp. 1031-1039
Citations number
39
Categorie Soggetti
Biology
ISSN journal
00142956
Volume
218
Issue
3
Year of publication
1993
Pages
1031 - 1039
Database
ISI
SICI code
0014-2956(1993)218:3<1031:COHALR>2.0.ZU;2-D
Abstract
Ciliary neurotrophic factor (CNTF) supports the survival of a wide var iety of neuronal cells in culture. To characterise the receptor(s) med iating the biological responses of CNTF we measured the binding of rad iolabelled CNTF to chick sympathetic neurons and human neuroblastoma c ells. Two distinct CNTF-binding sites with high and low affinity for t he ligand were identified by steady-state binding experiments. Further more, two low-affinity binding sites could be discriminated on the bas is of the dissociation rates. Cross-linking experiments showed that CN TF interacts with two proteins, one of 80 kDa and one of 140 kDa. The identity of the 80-kDa protein was determined by transient transfectio n experiments with the rat CNTF-binding protein CNTFRalpha while the p roperties of the 140-kDa protein correspond to those of gp130. Antisen se experiments confirmed that CNTTRalpha is necessary for high affinit y binding of I-125-CNTF and therefore a necessary subunit of the high- affinity receptor.