Cell-specific localization of the alpha-subunit of calcium/calmodulin-dependent protein kinase II in Purkinje cells in rodent cerebellum.
Brain calcium/calmodulin-dependent protein kinase type II, a multimeric 600-650 kDa enzyme composed of alpha- (50 kDa) and beta/beta' (60 and 58 kDa) subunits, may be formed by alpha- and beta-subunits combining in variable proportions in different types of neurons. This study presents evidence, using cerebella from mutant mice, that the alpha-subunit displays a restricted localization in the rodent cerebellum, being detectable only in Purkinje cells. Immunocytochemical analysis of normal rat cerebellum with an antibody selective for the alpha-subunit confirmed that this subunit was detectable only in Purkinje cells. In contrast, the beta/beta'-subunits appeared to be present in all types of cerebellar mutants examined. These results indicate that different cells of the cerebellum express distinct isozymic forms of the multifunctional calcium/calmodulin-dependent protein kinase type II. It appears that Purkinje cells primarily contain an isoenzyme formed by both alpha- and beta/beta'-subunits, and that non-Purkinje cells contain an isoenzyme formed primarily by beta/beta'-subunits.
Walaas
S I
SI
Laboratory of Molecular and Cellular Neuroscience, Rockefeller University, New York, NY 10021.
Lai
Y
Y
Gorelick
F S
FS
DeCamilli
P
P
Moretti
M
M
Greengard
P
P
D000818:Animals; D019703:Calcineurin; D002148:Calmodulin-Binding Proteins / Q000378:metabolism*; D002540:Cerebral Cortex / Q000201:enzymology; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male; D051379:Mice; D008818:Mice, Neurologic Mutants / Q000378:metabolism*; D008970:Molecular Weight; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D011689:Purkinje Cells / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D017871:Calcium-Calmodulin-Dependent Protein Kinases
D019703:Calcineurin; D002148:Calmodulin-Binding Proteins; D007527:Isoenzymes; D010749:Phosphoprotein Phosphatases; D011494:Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases