Multivalent coiled-coil interactions enable full-scale centrosome assembly and strength.
J Cell Biol
; 223(4)2024 04 01.
Article
em En
| MEDLINE
| ID: mdl-38456967
ABSTRACT
The outermost layer of centrosomes, called pericentriolar material (PCM), organizes microtubules for mitotic spindle assembly. The molecular interactions that enable PCM to assemble and resist external forces are poorly understood. Here, we use crosslinking mass spectrometry (XL-MS) to analyze PLK-1-potentiated multimerization of SPD-5, the main PCM scaffold protein in C. elegans. In the unassembled state, SPD-5 exhibits numerous intramolecular crosslinks that are eliminated after phosphorylation by PLK-1. Thus, phosphorylation induces a structural opening of SPD-5 that primes it for assembly. Multimerization of SPD-5 is driven by interactions between multiple dispersed coiled-coil domains. Structural analyses of a phosphorylated region (PReM) in SPD-5 revealed a helical hairpin that dimerizes to form a tetrameric coiled-coil. Mutations within this structure and other interacting regions cause PCM assembly defects that are partly rescued by eliminating microtubule-mediated forces, revealing that PCM assembly and strength are interdependent. We propose that PCM size and strength emerge from specific, multivalent coiled-coil interactions between SPD-5 proteins.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Caenorhabditis elegans
/
Centrossomo
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Proteínas de Ciclo Celular
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Quinase 1 Polo-Like
Limite:
Animals
Idioma:
En
Revista:
J Cell Biol
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Estados Unidos