Immunolocalization of the exocytosis-sensitive phosphoprotein, PP63/parafusin, in Paramecium cells using antibodies against recombinant protein.
We have localized a structure-bound fraction of the exocytosis-sensitive phosphoprotein, PP63/parafusin (PP63/pf), in Paramecium cells by widely different methods. We combined cell fractionation, western blots, as well as light and electron microscopy (pre- and post-embedding immunolabeling), applying antibodies against the recombinant protein. PP63/pf is considerably enriched in certain cortical structures, notably the outlines of regular surface fields (kinetids), docking sites of secretory organelles (trichocysts) and the membranes of subplasmalemmal Ca2+-stores (alveolar sacs). From our localization studies we tentatively derive several potential functions for PP63/pf, including cell surface structuring, assembly of exocytosis sites, and/or Ca2+ homeostasis.
Faculty of Biology, University of Konstanz, Germany.
R
R
Kissmehl
K
K
Hauser
M
M
Gössringer
M
M
Momayezi
N
N
Klauke
H
H
Plattner
D000818:Animals; D000906:Antibodies / Q000276:immunology; D015153:Blotting, Western; D002458:Cell Fractionation; D003911:Dextrans / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005089:Exocytosis / Q000502:physiology*; D019085:Fluorescent Antibody Technique, Direct; D007150:Immunohistochemistry; D010247:Paramecium / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D010733:Phosphoglucomutase; D010750:Phosphoproteins / Q000276:immunology / Q000378:metabolism*; D015800:Protozoan Proteins / Q000276:immunology / Q000378:metabolism*; D011994:Recombinant Proteins / Q000276:immunology; D013347:Subcellular Fractions / Q000378:metabolism / Q000648:ultrastructure
D000906:Antibodies; D003911:Dextrans; D010750:Phosphoproteins; D015800:Protozoan Proteins; D011994:Recombinant Proteins; C087273:parafusin protein, Paramecium; C039691:aminoethyldextran; D010733:Phosphoglucomutase