Characterization of two distinct populations of detergent resistant membrane complexes isolated from chick brain tissues.
We report the isolation of two distinct populations of detergent resistant membrane complexes (DRMCs) from 1-day-old chick brain, utilizing a procedure involving Triton X-100 insolubility and sucrose density gradient centrifugation. The first population is abundant (1.8% of the total homogenate protein), highly enriched for two glycosylphosphatidylinositol (GPI)-anchored proteins (Thy-1 and AvGp50), and not enriched for caveolin. The second population is of relatively low abundance (0.2% of the total homogenate), contains relatively low levels of Thy-1 and AvGp50 enrichment, and is highly enriched in caveolin. Both populations of DRMCs are enriched for cholesterol, ganglioside GM1, total kinase and tyrosine kinase activities, and c-Src and c-Fyn. However, there are differences in the Coomassie-stained protein profiles, phosphoprotein components, tyrosine kinase activity, and electron microscopic morphology when the Thy-1 and AvGp50-enriched DRMCs are compared to the caveolin-rich DRMCs. In addition, the GPI-enriched DRMCs contain CaM kinase type II immunoreactivity, whereas this molecule was undectable in the caveolin-rich DRMCs. The isolation of two distinct DRMC fractions may be representative of unique plasma membrane signaling domains involved in GPI-anchored protein or other receptor-mediated signal transduction within the avian nervous system. Further, we have demonstrated for the first time that nervous system tissue, in particular the hatch chick cerebellum, contains caveolin immunoreactivity.
Henke
R C
RC
Developmental Neurobiology Unit, Children's Medical Research Institute, Wentworthville, New South Wales, Australia.
Hancox
K A
KA
Jeffrey
P L
PL
D000818:Animals; D000911:Antibodies, Monoclonal; D015153:Blotting, Western; D001921:Brain / Q000648:ultrastructure*; D001923:Brain Chemistry / Q000502:physiology*; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D051242:Caveolin 1; D022461:Caveolins; D002499:Centrifugation, Density Gradient; D002645:Chickens / Q000378:metabolism*; D003902:Detergents; D017261:Glycosylphosphatidylinositols / Q000737:chemistry* / Q000502:physiology; D007150:Immunohistochemistry; D007518:Isoantibodies; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000502:physiology; D008565:Membrane Proteins / Q000378:metabolism; D008566:Membranes / Q000737:chemistry / Q000648:ultrastructure; D051379:Mice; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000502:physiology; D019000:Phosphotyrosine / Q000378:metabolism; D018800:Thy-1 Antigens / Q000737:chemistry / Q000502:physiology; D019061:src-Family Kinases / Q000378:metabolism
D000911:Antibodies, Monoclonal; C495541:Cav1 protein, mouse; D051242:Caveolin 1; D022461:Caveolins; D003902:Detergents; D017261:Glycosylphosphatidylinositols; D007518:Isoantibodies; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D018800:Thy-1 Antigens; C035678:anti-Thy antibody; C052914:brain synaptic membrane glycoprotein gp 50; D019000:Phosphotyrosine; D019061:src-Family Kinases; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases