Phosphorylation of a 70 kD Tetrahymena ciliary membrane protein is associated with ciliogenesis.
To identify proteins in Tetrahymena thermophila which were phosphorylated during ciliary assembly, the antiphosphoprotein antibody MPM-2 was used to probe blots of total ciliary protein or axonemal and ciliary membrane/matrix fractions from full-length cilia, regenerating cilia, or cilia that had grown to full-length following deciliation. A 70 kD protein was recognized by MPM-2 only in blots of total ciliary protein from regenerating cilia and of the membrane/matrix fraction from regenerating cilia. MPM-2 did not recognize this protein in blots of axonemal fractions of regenerating cilia or in blots of either axonemal or membrane/matrix fractions of full-length cilia. The results indicate that the 70 kD ciliary membrane protein was phosphorylated only in ciliary membranes or matrices of growing cilia. After the cilia reached full-length the membrane/matrix protein was either dephosphorylated or removed from the cilia. These observations support the hypothesis that the 70 kD membrane/matrix protein functions primarily during ciliary assembly.
Department of Zoology, Miami University, Oxford, Ohio 45056, USA.
D L
DL
Gitz
D G
DG
Pennock
D000818:Animals; D000911:Antibodies, Monoclonal; D002923:Cilia / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism*; D003049:Coccidiostats / Q000494:pharmacology; D004136:Dinitrobenzenes / Q000494:pharmacology; D008565:Membrane Proteins / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D010750:Phosphoproteins / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D010766:Phosphorylation; D013424:Sulfanilamides; D016808:Tetrahymena thermophila / Q000737:chemistry* / Q000378:metabolism* / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D003049:Coccidiostats; D004136:Dinitrobenzenes; D008565:Membrane Proteins; D010750:Phosphoproteins; D013424:Sulfanilamides; C012465:oryzalin