Myelin basic protein is a glial microtubule-associated protein -- characterization of binding domains, kinetics of polymerization, and regulation by phosphorylation and a lipidic environment.
Biochem Biophys Res Commun
; 461(1): 136-41, 2015 May 22.
Article
em En
| MEDLINE
| ID: mdl-25862371
ABSTRACT
The 18.5-kDa splice isoform of myelin basic protein (MBP) predominates in the adult brain, adhering the cytoplasmic leaflets of the oligodendrocyte membrane together, but also assembling the cytoskeleton at leading edges of membrane processes. Here, we characterized MBP's role as a microtubule-assembly protein (MAP). Using light scattering and sedimentation assays we found that pseudo-phosphorylation of Ser54 (murine 18.5-kDa sequence) significantly enhanced the rate but not the final degree of polymerization. This residue lies within a short KPGSG motif identical to one in tau, a ubiquitous MAP important in neuronal microtubule assembly. Using polypeptide constructs, each comprising one of three major amphipathic α-helical molecular recognition fragments of 18.5-kDa MBP, we identified the N-terminal α1-peptide as sufficient to cause microtubule polymerization, the rate of which was significantly enhanced in the presence of dodecylphosphocholine (DPC) micelles to mimic a lipidic environment.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fosforilcolina
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Tubulina (Proteína)
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Neuroglia
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Proteína Básica da Mielina
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Bicamadas Lipídicas
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Proteínas dos Microtúbulos
Tipo de estudo:
Risk_factors_studies
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article