Phosphorylation of tubulin enhances its interaction with membranes.
Tubulin, the main component of intracellular microtubules, is also a major protein in subcellular membrane preparations and can interact with biological and artificial membranes in vitro. Of particular interest is the association of tubulin with postsynaptic junctional lattices enriched in a polypeptide of relative molecular mass (Mr) 50,000 (50K), recently identified as the major subunit of the calmodulin-dependent protein kinase. Phosphorylation of tubulin with a calmodulin-dependent protein kinase similar to that found in postsynaptic densities inhibits its ability to self-assemble into microtubules in a reversible fashion. This involves the phosphorylation of residues in its 4K carboxy-terminal region, a domain that seems to regulate its self-assembly. The results presented here suggest that the phosphorylation of tubulin with this kinase enhances its ability to interact with membranes. This effect is reversible.
D000818:Animals; D001923:Brain Chemistry; D002147:Calmodulin / Q000378:metabolism; D007425:Intracellular Membranes / Q000378:metabolism*; D007527:Isoenzymes / Q000378:metabolism; D008958:Models, Molecular; D008970:Molecular Weight; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism; D013552:Swine; D014404:Tubulin / Q000378:metabolism*
D002147:Calmodulin; D007527:Isoenzymes; D014404:Tubulin; D011494:Protein Kinases