Related Experiment Video
Updated: Aug 18, 2026

Preparation of Synaptic Plasma Membrane and Postsynaptic Density Proteins Using a Discontinuous Sucrose Gradient
Published on: September 3, 2014
Solubility and posttranslational regulation of GP130/F11--a neuronal GPI-linked cell adhesion molecule enriched in
Abstract:
GP130 (renamed contactin) has previously been identified by its detergent insolubility and retention with the actin-containing "membrane skeleton" isolated from chicken neurons and brain. The contactin sequence predicted a transmembrane and cytoplasmic domain for the molecule. Recently, F11 was shown to have an identical sequence except for the C terminus, and it was predicted to be linked to the plasma membrane by a glycosylphosphatidylinositol (GPI) group. Here we describe that GP130 can be released both from brain membranes and the detergent-insoluble membrane skeleton by a phosphoinositol-specific phospholipase C (PI-PLC) indicating that F11 and GP130/contactin are probably identical and that surprisingly the lipid anchor is partly or totally responsible for its non-ionic detergent insolubility. The "membrane skeleton" is a rich source of GPI-linked glycoproteins as judged by 1) most glycoproteins can be released by a PI-PLC and 2) most [3H]ethanolamine-labeled glycoproteins are present in, or enriched in the membrane skeleton. Thus, detergent insolubility appears to be a characteristic of GPI-anchored glycoproteins. No evidence has been obtained that GP130/F11 is released or secreted in vivo or in culture. In addition, GP130/F11 has an unusually long half-life in culture of greater than 3 days. The structure of the neuronal membrane skeleton and the potential function of GPI-anchored glycoproteins is discussed.
Related Concept Videos
GTPases and their Regulation
Large G-proteins, also known...
GPI Anchoring of Proteins in the ER Membrane
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
Assembly of Signaling Complexes
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Activation and Inactivation of G Proteins
IP3/DAG Signaling Pathway
Intracellular Signaling Affects Focal Adhesions
Some...

