title: The structure of cell membranes involved in intercellular communication.
abstract: The molecular structure of mouse hepatocyte gap junctions is investigated with corrlated electron microscopy, biochemistry, and x-ray diffraction technics. These studies reveal that the gap junction is composed of a hexagonal lattice of protein subunits, connexons, which pierce the hydrophobic membrane and establish a structural basis for intercellular hydrophilic channels or pores. By digesting liver-cell membranes with trypsin, a preparation of open- and closed-gap junction vesicles can be generated; this preparation will permit direct permeability measurements across the gap junction membranes in an in-vitro system.
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000502:physiology / Q000648:ultrastructure*; D002463:Cell Membrane Permeability; D005614:Freeze Fracturing; D007365:Intercellular Junctions / Q000648:ultrastructure; D008099:Liver / Q000166:cytology / Q000648:ultrastructure; D051379:Mice; D008854:Microscopy, Electron; D011506:Proteins / Q000302:isolation & purification; D014357:Trypsin; D014961:X-Ray Diffraction
chemical_list: D011506:Proteins; D014357:Trypsin