| First Author | Kimura Y | Year | 2010 |
| Journal | J Biol Chem | Volume | 285 |
| Issue | 30 | Pages | 22936-41 |
| PubMed ID | 20519502 | Mgi Jnum | J:168379 |
| Mgi Id | MGI:4888104 | Doi | 10.1074/jbc.C110.128280 |
| Citation | Kimura Y, et al. (2010) Identification of tubulin deglutamylase among Caenorhabditis elegans and mammalian cytosolic carboxypeptidases (CCPs). J Biol Chem 285(30):22936-41 |
| abstractText | Tubulin polyglutamylation is a reversible post-translational modification, serving important roles in microtubule (MT)-related processes. Polyglutamylases of the tubulin tyrosine ligase-like (TTLL) family add glutamate moieties to specific tubulin glutamate residues, whereas as yet unknown deglutamylases shorten polyglutamate chains. First we investigated regulatory machinery of tubulin glutamylation in MT-based sensory cilia of the roundworm Caenorhabditis elegans. We found that ciliary MTs were polyglutamylated by a process requiring ttll-4. Conversely, loss of ccpp-6 gene function, which encodes one of two cytosolic carboxypeptidases (CCPs), resulted in elevated levels of ciliary MT polyglutamylation. Consistent with a deglutamylase function for ccpp-6, overexpression of this gene in ciliated cells decreased polyglutamylation signals. Similarly, we confirmed that overexpression of murine CCP5, one of two sequence orthologs of nematode ccpp-6, caused a dramatic loss of MT polyglutamylation in cultured mammalian cells. Finally, using an in vitro assay for tubulin glutamylation, we found that recombinantly expressed Myc-tagged CCP5 exhibited deglutamylase biochemical activities. Together, these data from two evolutionarily divergent systems identify C. elegans CCPP-6 and its mammalian ortholog CCP5 as a tubulin deglutamylase. |
