Atg23 and Atg27 act at the early stages of Atg9 trafficking in S. cerevisiae.
Traffic
; 16(2): 172-90, 2015 Feb.
Article
em En
| MEDLINE
| ID: mdl-25385507
ABSTRACT
Atg9 is a conserved multipass transmembrane protein with an essential role in autophagy. In Saccharomyces cerevisiae, it travels through the secretory pathway to a unique compartment, the Atg9 peripheral structures. These structures are then targeted to the phagophore assembly site (PAS), where they are proposed to help deliver membrane to the forming autophagosome. We used 'in vivo reconstitution' of this process in a multiple-knockout strain to define four proteins, Atg11, Atg19, Atg23 and Atg27, as the core minimal machinery necessary and sufficient for the trafficking of Atg9 to the PAS. Atg23 and Atg27 function in the formation of the Atg9 peripheral structures. Overexpression of Atg9 can bypass the need for Atg23, suggesting that the amount of Atg9 in each peripheral structure is a critical factor in their targeting to the PAS. In contrast, overexpression of Atg23 or Atg27 interferes with Atg9 trafficking, suggesting that these proteins must be present in the appropriate stoichiometry in order to function properly. These data allow us to resolve existing controversies regarding the role of Atg23 and Atg27, and propose a model that ties together previous observations regarding the role of Atg9 in autophagosome formation.
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Texto completo:
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Bases de dados:
MEDLINE
Assunto principal:
Saccharomyces cerevisiae
/
Proteínas de Transporte
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Proteínas de Saccharomyces cerevisiae
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Proteínas de Membrana
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Traffic
Assunto da revista:
FISIOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Estados Unidos