A combination of posttranslational modifications is responsible for the production of neuronal α-tubulin heterogeneity
| Autor: | Philippe Denoulet, Yoheved Berwald-Netter, Annette Koulakoff, J.P. Le Caer, Bernard Eddé, Jérôme Rossier, François Gros |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Molecular Sequence Data
Glutamic Acid macromolecular substances Biochemistry Mice Glutamates Acetyltransferases Tubulin Microtubule Animals Amino Acid Sequence Molecular Biology Peptide sequence Cells Cultured Chromatography High Pressure Liquid Brain Chemistry Neurons Edman degradation biology Isoelectric focusing Chlamydomonas Brain Acetylation Cell Biology Polyglycylation Astrocytes Acetyltransferase biology.protein Microtubule-Associated Proteins Protein Processing Post-Translational |
| Zdroj: | Journal of Cellular Biochemistry. 46:134-142 |
| ISSN: | 1097-4644 0730-2312 |
| DOI: | 10.1002/jcb.240460207 |
| Popis: | We describe the presence of alpha-tubulin and MAP2 acetyltransferase activities in mouse brain. The enzyme(s) copurified with microtubules through two cycles of assembly-disassembly. Incubation of microtubule proteins with [3H]acetyl CoA resulted in a strong labeling of both alpha-tubulin and MAP2. To determine the site of the modification, tubulin was purified and digested with Glu-C endoproteinase. A unique radioactive peptide was detected and purified by HPLC. Edman degradation sequencing showed that this peptide contained epsilon N-acetyllysine at position 40 of the alpha-tubulin molecule. This result demonstrates that mouse brain alpha-tubulin was acetylated at the same site as in Chlamydomonas. Isoelectric focusing analysis showed that acetylated alpha-tubulin was resolved into five isoelectric variants, denoted alpha 3 and alpha 5 to alpha 8. This heterogeneity is not due to acetylation of other sites but results from a single acetylation of Lys40 of an heterogeneous population of alpha-tubulin isoforms. These isoforms are produced by posttranslational addition of one to five glutamyl units. Thus, neuronal alpha-tubulin is extensively modified by a combination of modifications including acetylation, glutamylation, tyrosylation, and other yet unknown modifications. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text