Tubular crystals of acetylcholine receptor.
J Cell Biol
; 99(4 Pt 1): 1202-11, 1984 Oct.
Article
em En
| MEDLINE
| ID: mdl-6480689
ABSTRACT
Well-ordered tubular crystals of acetylcholine receptor were obtained from suspensions of Torpedo marmorata receptor-rich vesicles. They are composed of pairs of oppositely oriented molecules arranged on the surface lattice with the symmetry of the plane group p2 (average unit cell dimensions a = 90 A, b = 162 A, gamma = 117 degrees). The receptor in this lattice has an asymmetric distribution of mass around its perimeter, yet a regular pentagonal shape; thus its five transmembrane subunits appear to have different lengths, but approximately equal cross sections. The tubes grow by lateral aggregation on the vesicle surface of ribbons of the paired molecules. Both ribbons and tubes were sensitive to dispersal by the disulphide reductant, dithiothreitol. This observation and other evidence suggest that the basic pairing interaction in the tubes may be that of the physiological dimer, involving contact between delta-subunits.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Receptores Colinérgicos
/
Órgão Elétrico
Limite:
Animals
Idioma:
En
Ano de publicação:
1984
Tipo de documento:
Article