Linked Life Data

17087732

Source:http://linkedlifedata.com/resource/pubmed/id/17087732

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2007-3-26
pubmed:abstractText
The etiologic agent of Q fever Coxiella burnetii, is an intracellular obligate parasite that develops large vacuoles with phagolysosomal characteristics, containing multiple replicating bacteria. We have previously shown that Phase II C. burnetii replicative vacuoles generated after 24-48 h post infection are decorated with the autophagic protein LC3. The aim of the present study was to examine, at earlier stages of infection, the distribution and roles of the small GTPases Rab5 and Rab7, markers of early and late endosomes respectively, as well as of the protein LC3 on C. burnetii trafficking. Our results indicate that: (i) Coxiella phagosomes (Cph) acquire the two Rab proteins sequentially during infection; (ii) overexpression of a dominant negative mutant form of Rab5, but not of Rab7, impaired Coxiella entry, whereas both Rab5 and Rab7 dominant negative mutants inhibited vacuole formation; (iii) Cph colocalized with the protein LC3 as early as 5 min after infection; acquisition of this protein appeared to be a bacterially driven process, because it was inhibited by the bacteriostatic antibiotic chloramphenicol and (iv) C. burnetii delayed the arrival of the typical lysosomal protease cathepsin D to the Cph, which delay is further increased by starvation-induced autophagy. Based on our results we propose that C. burnetii transits through the normal endo/phagocytic pathway but actively interacts with autophagosomes at early times after infection. This intersection with the autophagic pathway delays fusion with the lysosomal compartment possibly favouring the intracellular differentiation and survival of the bacteria.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1462-5814
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
891-909
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
The autophagic pathway is actively modulated by phase II Coxiella burnetii to efficiently replicate in the host cell.
pubmed:affiliation
Laboratorio de Biología Celular y Molecular, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo--Mendoza, 5500, Argentina.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't