Characterization of polyclonal antibodies to brain protein phosphatase 2A and immunohistochemical localization of the enzyme in rat brain.
Polyclonal antibodies to the catalytic subunit of protein phosphatase 2A (PrP-2A) from bovine brain were prepared by immunizing rabbits and then purified by antigen-affinity column chromatography. The purified antibodies recognized only PrP-2A among proteins examined, including calcineurin and PrP-1. The antibodies cross-reacted only with a protein in the crude homogenate from rat brain, which comigrated with the catalytic subunit of PrP-2A on SDS-PAGE. The antibodies completely inhibited the activity of PrP-2A, and immunoprecipitated the purified enzyme. Immunoblot analysis demonstrates that, among the subcellular fractions from rat brain, the cytosol fraction and the synaptosomal cytosol fraction show high immunoreactivities, and that any of examined regions of rat brain shows immunoreactivity more or less, in which the caudatoputamen was highest. Immunohistochemical studies demonstrate that the enzyme is distributed widely in various regions of rat brain and that the immunoreactivity is localized mainly in neurons. In general, immunostaining of neurons was strong in neurites as well as somata. It was noted that intracerebellar nuclei were strongly stained in both neuronal somata and dendrites. Amygdaloid complex, thalamus, neocortex, hippocampal formation, and caudatoputamen were moderately stained.
Saitoh
Y
Y
Department of Neurosurgery, Kumamoto University Medical School, Japan.
Yamamoto
H
H
Ushio
Y
Y
Miyamoto
E
E
D000818:Animals; D000918:Antibody Specificity; D001921:Brain / Q000201:enzymology*; D007106:Immune Sera / Q000032:analysis*; D007150:Immunohistochemistry; D010749:Phosphoprotein Phosphatases / Q000276:immunology* / Q000378:metabolism; D054648:Protein Phosphatase 2; D051381:Rats; D011919:Rats, Inbred Strains
D007106:Immune Sera; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2