The myelin-axolemmal complex: biochemical dissection and the role of galactosphingolipids.
Myelin-axolemmal interactions regulate many cellular and molecular events, including gene expression, oligodendrocyte survival and ion channel clustering. Here we report the biochemical fractionation and enrichment of distinct subcellular domains from myelinated nerve fibers. Using antibodies against proteins found in compact myelin, non-compact myelin and axolemma, we show that a rigorous procedure designed to purify myelin also results in the isolation of the myelin-axolemmal complex, a high-affinity protein complex consisting of axonal and oligodendroglial components. Further, the isolation of distinct subcellular domains from galactolipid-deficient mice with disrupted axoglial junctions is altered in a manner consistent with the delocalization of axolemmal proteins observed in these animals. These results suggest a paradigm for identification of proteins involved in neuroglial signaling.
Menon
Krishna
K
Department of Neuroscience, University of Connecticut Medical School, Farmington, Connecticut 06030-3401, USA.
Rasband
Matthew N
MN
Taylor
Christopher M
CM
Brophy
Peter
P
Bansal
Rashmi
R
Pfeiffer
Steven E
SE
D000818:Animals; D001923:Brain Chemistry; D002499:Centrifugation, Density Gradient; D004591:Electrophoresis, Polyacrylamide Gel; D005690:Galactose / Q000737:chemistry; D006028:Glycosphingolipids / Q000737:chemistry* / Q000502:physiology*; D015151:Immunoblotting; D007150:Immunohistochemistry; D046911:Macromolecular Substances; D051379:Mice; D009186:Myelin Sheath / Q000737:chemistry*; D009413:Nerve Fibers, Myelinated / Q000737:chemistry; D009900:Optic Nerve / Q000166:cytology; D013347:Subcellular Fractions / Q000737:chemistry
D006028:Glycosphingolipids; D046911:Macromolecular Substances; D005690:Galactose