Characterization and cellular localization of a developmentally regulated rat neural sialidase.
A developmentally regulated neural sialidase has been identified in particulate, subcellular fractions of rat brain. Enzyme activity, measured using a [3H]sialoganglioside substrate, was linear with time and had a pH optimum of 4.0-4.5. Protein linearity was only observed at low protein concentrations. This appeared to be caused by enzyme access to a lipophilic substrate, as activity was significantly stimulated by membrane-fluidizing agents. Enzyme activity was developmentally expressed in P2 pellets coincident with in vivo synaptogenesis. It was located on the synaptosome and was particularly high in myelin-containing fractions. Its cellular distribution was confined to neuronal cells and centrally derived oligodendrocytes.
N M
NM
Moran
K C
KC
Breen
C M
CM
Regan
D000818:Animals; D001921:Brain / Q000166:cytology / Q000201:enzymology* / Q000254:growth & development; D008566:Membranes / Q000201:enzymology; D009439:Neuraminidase / Q000378:metabolism*; D009474:Neurons / Q000201:enzymology; D051381:Rats / Q000254:growth & development; D011919:Rats, Inbred Strains; D013347:Subcellular Fractions / Q000201:enzymology; D014018:Tissue Distribution
D009439:Neuraminidase