V. Horejsi et al., ASSOCIATION OF GPI-ANCHORED GLYCOPROTEINS WITH OTHER COMPONENTS OF THE LEUKOCYTE MEMBRANE, Brazilian journal of medical and biological research, 27(2), 1994, pp. 255-262
The leucocyte surface glycosylphosphatidylinositol (GPI)-anchored memb
rane proteins are localized within specific membrane microdomains whic
h also contain specific (glyco)lipids and intracellular proteins inclu
ding protein kinases. These ''GPI-domains'' are devoid of most abundan
t transmembrane proteins, but in T-cells they appear to contain small
amounts of CD4 and CD8 and in B-cell lines, small amounts of CD10. The
existence of these relatively detergent-resistant membrane microdomai
ns explains the signal-transducing ability of GPI-anchored receptors.
In addition to the ''GPI-microdomains'', several other types of analog
ous very large detergent-resistant complexes/domains appear to exist,
such as those containing T-cell receptor, others containing CD45R mole
cules associated with a protein kinase, and still others composed main
ly of several proteins of the tetraspan family. Therefore, we suggest
that the leucocyte surface is a mosaic of microdomains of unique compo
sition associated with specific signal-transducing molecules.