PLK4 is a microtubule-associated protein that self-assembles promoting de novo MTOC formation.
J Cell Sci
; 132(4)2018 11 09.
Article
in En
| MEDLINE
| ID: mdl-30237222
ABSTRACT
The centrosome is an important microtubule-organising centre (MTOC) in animal cells. It consists of two barrel-shaped structures, the centrioles, surrounded by the pericentriolar material (PCM), which nucleates microtubules. Centrosomes can form close to an existing structure (canonical duplication) or de novo How centrosomes form de novo is not known. The master driver of centrosome biogenesis, PLK4, is critical for the recruitment of several centriole components. Here, we investigate the beginning of centrosome biogenesis, taking advantage of Xenopus egg extracts, where PLK4 can induce de novo MTOC formation ( Eckerdt et al., 2011; Zitouni et al., 2016). Surprisingly, we observe that in vitro, PLK4 can self-assemble into condensates that recruit α- and ß-tubulins. In Xenopus extracts, PLK4 assemblies additionally recruit STIL, a substrate of PLK4, and the microtubule nucleator γ-tubulin, forming acentriolar MTOCs de novo The assembly of these robust microtubule asters is independent of dynein, similar to what is found for centrosomes. We suggest a new mechanism of action for PLK4, where it forms a self-organising catalytic scaffold that recruits centriole components, PCM factors and α- and ß-tubulins, leading to MTOC formation.This article has an associated First Person interview with the first author of the paper.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Protein Serine-Threonine Kinases
/
Cell Cycle Proteins
/
Microtubule-Organizing Center
/
Xenopus Proteins
/
Microtubule-Associated Proteins
/
Microtubules
Type of study:
Risk_factors_studies
Limits:
Animals
Language:
En
Journal:
J Cell Sci
Year:
2018
Document type:
Article