The AAA3 domain of cytoplasmic dynein acts as a switch to facilitate microtubule release.
Nat Struct Mol Biol
; 22(1): 73-80, 2015 Jan.
Article
em En
| MEDLINE
| ID: mdl-25486306
ABSTRACT
Cytoplasmic dynein is an AAA+ motor responsible for intracellular cargo transport and force generation along microtubules (MTs). Unlike kinesin and myosin, dynein contains multiple ATPase subunits, with AAA1 serving as the primary catalytic site. ATPase activity at AAA3 is also essential for robust motility, but its role in dynein's mechanochemical cycle remains unclear. Here, we introduced transient pauses in Saccharomyces cerevisiae dynein motility by using a slowly hydrolyzing ATP analog. Analysis of pausing behavior revealed that AAA3 hydrolyzes nucleotide an order of magnitude more slowly than AAA1, and the two sites do not coordinate. ATPase mutations to AAA3 abolish the ability of dynein to modulate MT release. Nucleotide hydrolysis at AAA3 lifts this 'MT gate' to allow fast motility. These results suggest that AAA3 acts as a switch that repurposes cytoplasmic dynein for fast cargo transport and MT-anchoring tasks in cells.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Saccharomyces cerevisiae
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Substâncias Macromoleculares
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Dineínas do Citoplasma
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Microtúbulos
Idioma:
En
Revista:
Nat Struct Mol Biol
Ano de publicação:
2015
Tipo de documento:
Article