RRC ID |
29062
|
著者 |
Fajardo M, Schleicher M, Noegel A, Bozzaro S, Killinger S, Heuner K, Hacker J, Steinert M.
|
タイトル |
Calnexin, calreticulin and cytoskeleton-associated proteins modulate uptake and growth of Legionella pneumophila in Dictyostelium discoideum.
|
ジャーナル |
Microbiology (Reading)
|
Abstract |
The haploid amoeba Dictyostelium discoideum is a versatile host system for studying cellular aspects of Legionella pathogenicity. Previous studies have shown that the internalization of L. pneumophila leads to an endoplasmic reticulum (ER)-derived organelle that supports intracellular replication of the bacteria. In this study a roadmap of host-cell factors involved in this process was developed. Phagocytosis assays with specific cellular inhibitors and the effects of well defined host-cell mutants revealed that cytoplasmic calcium levels, cytoskeleton-associated proteins and the calcium-binding proteins of the ER, calreticulin and calnexin, specifically influence the uptake and intracellular growth of L. pneumophila. Confocal microscopic time series with green fluorescent protein (GFP)-tagged calnexin and calreticulin demonstrated the accumulation of both proteins in the phagocytic cup of L. pneumophila-infected host cells. In contrast to the control experiment with Escherichia coli-containing phagosomes, both proteins decorated the replicative vacuole of L. pneumophila during the entire growth phase of the bacteria. The cumulative effects of cytosolic calcium levels, the spatial distribution of calnexin and calreticulin, and the defective invasion and replication of L. pneumophila in calnexin- and calreticulin-minus cells suggest that these factors are part of a regulatory system that leads to the specific vacuole of L. pneumophila.
|
巻・号 |
150(Pt 9)
|
ページ |
2825-2835
|
公開日 |
2004-9-1
|
DOI |
10.1099/mic.0.27111-0
|
PMID |
15347742
|
MeSH |
Animals
Artificial Gene Fusion
Calcium / physiology
Calcium-Binding Proteins / physiology
Calnexin / genetics
Calnexin / physiology*
Calreticulin / genetics
Calreticulin / physiology*
Colony Count, Microbial
Cytoplasm / chemistry
Cytoskeleton / physiology*
Dictyostelium / drug effects
Dictyostelium / genetics
Dictyostelium / metabolism
Dictyostelium / microbiology*
Gene Deletion
Genes, Reporter
Legionella pneumophila / growth & development*
Legionella pneumophila / metabolism
Legionella pneumophila / pathogenicity
Microscopy, Confocal
Mutation
Phagocytosis / drug effects
Protozoan Proteins / physiology
Recombinant Fusion Proteins / metabolism
Vacuoles / chemistry
Vacuoles / microbiology
Vacuoles / ultrastructure
|
IF |
2.138
|
引用数 |
50
|
WOS 分野
|
MICROBIOLOGY
|
リソース情報 |
細胞性粘菌 |
S90291 |