Extracellular domain of neurotrophin receptor trkB: disulfide structure, N-glycosylation sites, and ligand binding.
An extracellular domain of a human neurotrophin receptor trkB was expressed in Chinese hamster ovary cells and isolated as a glycoprotein possessing binding activity for brain-derived neurotrophic factor. The extracellular domain contains 398 amino acids and has a molecular weight of 60.6 kDa according to laser desorption mass spectrometry, indicating that the extracellular domain of trkB contains 33.3% carbohydrate moieties. Six disulfide linkages were determined to be Cys1-Cys7, Cys5-Cys14, Cys121-Cys145, Cys123-Cys163, Cys187-Cys235, and Cys271-Cys314, respectively. Cys300 was detected as a free sulfhydryl residue. Cysteine clusters 1 and 2 located in the N-terminal domain possess a similar type of disulfide structure and two other disulfide bonds in the C-terminal region are homologous to that of the Ig-like C2 domain. Among 12 potential N-linked glycosylation sites proposed in the soluble domain of trkB, 10 sites are actually glycosylated.
Haniu
M
M
Amgen, Inc., Thousand Oaks, California 91320, USA.
Talvenheimo
J
J
Le
J
J
Katta
V
V
Welcher
A
A
Rohde
M F
MF
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D016466:CHO Cells; D006224:Cricetinae; D003432:Cross-Linking Reagents; D004220:Disulfides / Q000737:chemistry; D006031:Glycosylation; D006801:Humans; D008024:Ligands; D008969:Molecular Sequence Data; D015394:Molecular Structure; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics; D010449:Peptide Mapping; D020801:Receptor, Ciliary Neurotrophic Factor; D017475:Receptors, Nerve Growth Factor / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D012995:Solubility
D003432:Cross-Linking Reagents; D004220:Disulfides; D008024:Ligands; D010446:Peptide Fragments; D020801:Receptor, Ciliary Neurotrophic Factor; D017475:Receptors, Nerve Growth Factor