Publication Date:
2022-05-25
Description:
Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Cell Motility and the Cytoskeleton 66 (2009): 650-660, doi:10.1002/cm.20387.
Description:
Post-translational protein modification occurs extensively in eukaryotic flagella. Here we
examine protein methylation, a protein modification that has only recently been reported to occur
in flagella (Schneider et al. 2008). The cobalamin (vitamin B12) independent form of the
enzyme methionine synthase (MetE), which catalyzes the final step in methionine production, is
localized to flagella. Here we demonstrate, using immunogold scanning electron microscopy,
that MetE is bound to the outer doublets of the flagellum. Methionine can be converted to Sadenosyl
methionine, which then serves as the methyl donor for protein methylation reactions.
Using antibodies that recognize symmetrically or asymmetrically methylated arginine residues,
we identify three highly methylated proteins in intact flagella: two symmetrically methylated
proteins of about 30 and 40 kDa, and one asymmetrically methylated protein of about 75 kDa.
Several other relatively less methylated proteins could also be detected. Fractionation and
immunoblot analysis shows that these proteins are components of the flagellar axoneme.
Immunogold thin section electron microscopy indicates that the symmetrically methylated
proteins are located in the central region of the axoneme, perhaps as components of the central
pair complex and the radial spokes, while the asymmetrically methylated proteins are associated
with the outer doublets.
Description:
This work was supported by NIH DK071720 (rds) and NSF MCB 0418877 (rds).
Keywords:
Flagella
;
Protein methylation
;
Chlamydomonas
;
Immunogold EM
Repository Name:
Woods Hole Open Access Server
Type:
Preprint
Format:
application/pdf
Permalink
