title: [Conserved and variable segments of amino acid sequences in alpha-subunits of nicotinic acetylcholine receptors and alpha-bungarotoxin-binding proteins].
abstract: A comparative study has been carried out of homologous amino acid sequences of alpha-subunits of acetylcholine receptors (AChR) and related proteins classified into three groups: (i) alpha-bungarotoxin-binding alpha-subunits of nicotine AChR from vertebrate muscles and electrical organ of the skate; (ii) alpha-bungarotoxin-binding alpha-subunits of neuronal AChR from chicken and rat brain and (iii) alpha-bungarotoxin-binding alpha-subunit of chicken brain proteins. The experimental results were plotted as intergroup variability profiles obtained by comparison of all the sequences within one group with each of the sequences in the other group. All of the local variability profiles appeared to be similar and contained both highly conservative and highly variable sites. To the former one may relate the transmembrane segments M1, M3 and, particularly, M2 as well as the 81-100 domain comprising several links pertaining to the ligand-binding domain in AChR. Domains 153-171 and 177-197 comprising most of the identified links involved in the binding of low molecular weight agonists and of alpha-bungarotoxin appeared to be highly variable ones.
authors.forename: P V
authors.initials: PV
authors.lastname: Kostetskiĭ
authors.forename: S F
authors.initials: SF
authors.lastname: Arkhipova
authors.forename: Iu N
authors.initials: IuN
authors.lastname: Utkin
authors.forename: V I
authors.initials: VI
authors.lastname: Tsetlin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002038:Bungarotoxins / Q000378:metabolism*; D002417:Cattle; D002645:Chickens; D017124:Conserved Sequence; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry* / Q000378:metabolism; D051381:Rats; D011978:Receptors, Nicotinic / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D014101:Torpedo; D064569:alpha7 Nicotinic Acetylcholine Receptor
chemical_list: D002038:Bungarotoxins; C579167:Chrna7 protein, human; C579166:Chrna7 protein, mouse; C579165:Chrna7 protein, rat; D009419:Nerve Tissue Proteins; D011978:Receptors, Nicotinic; D064569:alpha7 Nicotinic Acetylcholine Receptor
vernacular_title: Konservativnye i variabel'nye uchastki aminokislotnykh posledovatel'nosteĭ v alpha-sub''edinitsakh nikotinovykh atsetilkholinovykh retseptorov i alpha-bungarotoksinsviazyvaiushchikh belkov.