Association of Legionella pneumophila with the macrophage endoplasmic reticulum.
AUTOR(ES)
Swanson, M S
RESUMO
Legionella pneumophila replicates within a membrane-bounded compartment that is studded with ribosomes. In this study we investigated whether these ribosomes originate from the cytoplasmic pool or are associated with host endoplasmic reticulum (ER). Immunofluorescence and electron microscopic localization studies of ER proteins in macrophages infected with L. pneumophila indicated that the bacteria reside in a compartment surrounded by ER. An L. pneumophila mutant that grows slowly in macrophages was slow to associate with host ER, providing genetic evidence in support of the hypothesis that this specialized vacuole is required for intracellular bacterial growth. Ultrastructural studies, in which the ER luminal protein BiP was labeled by immunoperoxidase cytochemistry, revealed that L. pneumophila replication vacuoles resemble nascent autophagosomes. Furthermore, short-term amino acid starvation of macrophages, which stimulated host autophagosomes. Furthermore, short-term amino acid starvation of macrophages, which stimulated host autophagy, increased association of the bacteria with the ER and enhanced bacterial growth. These results are compatible with the hypothesis that L. pneumophila exploits the autophagy machinery of macrophages to establish an intracellular niche favorable for replication.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=173501Documentos Relacionados
- Association of poliovirus proteins with the endoplasmic reticulum.
- The phagosome containing Legionella pneumophila within the protozoan Hartmannella vermiformis is surrounded by the rough endoplasmic reticulum.
- Coatomer-rich endoplasmic reticulum.
- "BFA bodies": a subcompartment of the endoplasmic reticulum.
- Intrinsic membrane glycoproteins with cytosol-oriented sugars in the endoplasmic reticulum.