Comparative Proteomics of Purified Pathogen Vacuoles Correlates Intracellular Replication of Legionella pneumophila with the Small GTPase Ras-related protein 1 (Rap1).
Mol Cell Proteomics
; 16(4): 622-641, 2017 04.
Article
em En
| MEDLINE
| ID: mdl-28183814
ABSTRACT
Legionella pneumophila is an opportunistic bacterial pathogen that causes a severe lung infection termed "Legionnaires' disease." The pathogen replicates in environmental protozoa as well as in macrophages within a unique membrane-bound compartment, the Legionella-containing-vacuole (LCV). LCV formation requires the bacterial Icm/Dot type IV secretion system, which translocates ca. 300 "effector proteins" into host cells, where they target distinct host factors. The L. pneumophila "pentuple" mutant (Δpentuple) lacks 5 gene clusters (31% of the effector proteins) and replicates in macrophages but not in Dictyostelium discoideum amoeba. To elucidate the host factors defining a replication-permissive compartment, we compare here the proteomes of intact LCVs isolated from D. discoideum or macrophages infected with Δpentuple or the parental strain Lp02. This analysis revealed that the majority of host proteins are shared in D. discoideum or macrophage LCVs containing the mutant or the parental strain, respectively, whereas some proteins preferentially localize to distinct LCVs. The small GTPase Rap1 was identified on D. discoideum LCVs containing strain Lp02 but not the Δpentuple mutant and on macrophage LCVs containing either strain. The localization pattern of active Rap1 on D. discoideum or macrophage LCVs was confirmed by fluorescence microscopy and imaging flow cytometry, and the depletion of Rap1 by RNA interference significantly reduced the intracellular growth of L. pneumophila Thus, comparative proteomics identified Rap1 as a novel LCV host component implicated in intracellular replication of L. pneumophila.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
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Vacúolos
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Legionella pneumophila
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Proteínas Monoméricas de Ligação ao GTP
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Proteínas rap1 de Ligação ao GTP
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Proteômica
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Dictyostelium
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Macrófagos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article