Molecular crowding facilitates bundling of IMPDH polymers and cytoophidium formation.
Cell Mol Life Sci
; 79(8): 420, 2022 Jul 14.
Article
em En
| MEDLINE
| ID: mdl-35833994
ABSTRACT
The cytoophidium is a unique type of membraneless compartment comprising of filamentous protein polymers. Inosine monophosphate dehydrogenase (IMPDH) catalyzes the rate-limiting step of de novo GTP biosynthesis and plays critical roles in active cell metabolism. However, the molecular regulation of cytoophidium formation is poorly understood. Here we show that human IMPDH2 polymers bundle up to form cytoophidium-like aggregates in vitro when macromolecular crowders are present. The self-association of IMPDH polymers is suggested to rely on electrostatic interactions. In cells, the increase of molecular crowding with hyperosmotic medium induces cytoophidia, while the decrease of that by the inhibition of RNA synthesis perturbs cytoophidium assembly. In addition to IMPDH, CTPS and PRPS cytoophidium could be also induced by hyperosmolality, suggesting a universal phenomenon of cytoophidium-forming proteins. Finally, our results indicate that the cytoophidium can prolong the half-life of IMPDH, which is proposed to be one of conserved functions of this subcellular compartment.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Polímeros
/
Espaço Intracelular
/
IMP Desidrogenase
Limite:
Humans
Idioma:
En
Revista:
Cell Mol Life Sci
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
China