Domain structure and signal transduction mechanisms in the thyrotropin receptor
Nagayama, Y.
Nihon Rinsho. Japanese Journal of Clinical Medicine 52(4): 979-983
1994
ISSN/ISBN: 0047-1852 PMID: 8196190 Document Number: 429179
The thyrotropin receptor is a single polypeptide (744 amino acids) consisting of two domains (N-terminal extracellular domain and C-terminal transmembrane/cytoplasmic region). The former (398 aa) contains six potential glycosylation sites, 11 cysteins and 9 leucine rich repeats and is very likely to be the major TSH binding site. On the other hand, the latter (346 aa) has a characteristic of G protein coupled receptors (seven transmembrane segments, 3 extracellular-and cyto-plasmic loops and a carboxyl terminal tail), contains potential phosphorylation sites (serine/threonine residues) for c-kinase and G-protein coupled receptor kinase and plays important roles in signal transduction and homologous desensitization. Experimentally-produced and naturally-occurring mutant receptors provide molecular mechanisms of receptor function.