Title

Junctional plasma membrane domains isolated from aggregating Dictyostelium discoideum amebae

UMMS Affiliation

Department of Cell Biology

Date

7-1-1986

Document Type

Article

Subjects

Animals; Cell Adhesion; *Cell Aggregation; Cell Fractionation; Cell Membrane; Dictyostelium; Membrane Proteins; Microscopy, Electron; Molecular Weight

Disciplines

Cell Biology | Life Sciences | Medicine and Health Sciences

Abstract

Regions of plasma membrane involved in Dictyostelium discoideum intercellular adhesion resist solubilization with the nonionic detergent Triton X-100. Electron microscopy shows that these regions of the plasma membrane adhere to each other, forming many bi- and multilamellar structures. NaDodSO4/polyacrylamide gels of these regions contain major polypeptides at 225 kDa (residual myosin), 105 kDa, 88 kDa, 84 kDa, 47 kDa (residual actin), and 34 kDa. These membranes contain a subset of the total plasma membrane proteins, as analyzed by labeling of electrophoretically fractionated and blotted membrane proteins with radioiodinated Con A and by electrophoresis of membrane proteins from surface-labeled cells. Antibodies specific for gp80, a glycoprotein implicated in intercellular adhesion, intensely stain the 88-kDa and 84-kDa bands. Since these membrane regions resist Triton extraction, they appear to be stabilized by protein-protein interactions. Such stabilizing interactions may involve multivalent linkages with adjacent cells, or associations with intracellular actin and myosin, or both. Since these membranes appear to represent regions of intercellular contact, we call them "contact regions."

Rights and Permissions

Citation: Proc Natl Acad Sci U S A. 1986 Jul;83(13):4779-83.

Related Resources

Link to article in PubMed

PubMed ID

3460072