A study of the organellar Ca2(+)-transport ATPase isozymes in pig cerebellar Purkinje neurons.
Pig cerebellar Purkinje neurons express a high level of Ca2(+)-transport ATPases in their intracellular Ca2+ stores. This was shown at the mRNA level by Northern blotting and in situ hybridization and at the protein level by Western blotting and immunocytochemistry. The majority of the Ca2(+)-transport ATPases in these neurons belongs to the SERCA2b type (i.e., the Ca2(+)-pump isoform found in most nonmuscle cells). The SERCA2a (cardiac/slow-twitch skeletal/smooth muscle) Ca2(+)-pump isoform is expressed only at very low levels. The main Ca2(+)-pump messenger is 6.0 kilobases long and belongs to a class 4-type processing of SERCA2, which is exclusively confined to the cerebrum and cerebellum. Phospholamban, a regulator of the SERCA2 Ca2(+)-transport ATPase in cardiac/slow-twitch skeletal/smooth muscle, could not be detected in Purkinje neurons.
Plessers
L
L
Laboratorium voor Fysiologie, Campus Gasthuisberg, Katholicke Universiteit Leuven, Belgium.
Eggermont
J A
JA
Wuytack
F
F
Casteels
R
R
D000818:Animals; D000911:Antibodies, Monoclonal; D016375:Antisense Elements (Genetics); D000252:Calcium-Transporting ATPases / Q000032:analysis / Q000235:genetics*; D002462:Cell Membrane / Q000201:enzymology; D007124:Immunoenzyme Techniques; D009693:Nucleic Acid Hybridization; D015388:Organelles / Q000201:enzymology* / Q000648:ultrastructure; D011689:Purkinje Cells / Q000166:cytology / Q000201:enzymology*; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D013552:Swine
D000911:Antibodies, Monoclonal; D016375:Antisense Elements (Genetics); D012333:RNA, Messenger; D000252:Calcium-Transporting ATPases