CLASPs stabilize the pre-catastrophe intermediate state between microtubule growth and shrinkage.
J Cell Biol
; 222(7)2023 07 03.
Article
em En
| MEDLINE
| ID: mdl-37184584
ABSTRACT
Cytoplasmic linker-associated proteins (CLASPs) regulate microtubules in fundamental cellular processes. CLASPs stabilize dynamic microtubules by suppressing microtubule catastrophe and promoting rescue, the switch-like transitions between growth and shrinkage. How CLASPs specifically modulate microtubule transitions is not understood. Here, we investigate the effects of CLASPs on the pre-catastrophe intermediate state of microtubule dynamics, employing distinct microtubule substrates to mimic the intermediate state. Surprisingly, we find that CLASP1 promotes the depolymerization of stabilized microtubules in the presence of GTP, but not in the absence of nucleotide. This activity is also observed for CLASP2 family members and a minimal TOG2-domain construct. Conversely, we find that CLASP1 stabilizes unstable microtubules upon tubulin dilution in the presence of GTP. Strikingly, our results reveal that CLASP1 drives microtubule substrates with vastly different inherent stabilities into the same slowly depolymerizing state in a nucleotide-dependent manner. We interpret this state as the pre-catastrophe intermediate state. Therefore, we conclude that CLASPs suppress microtubule catastrophe by stabilizing the intermediate state between growth and shrinkage.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Proteínas Associadas aos Microtúbulos
/
Microtúbulos
Idioma:
En
Revista:
J Cell Biol
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Estados Unidos