Linked Life Data

16085396

Source:http://linkedlifedata.com/resource/pubmed/id/16085396

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2005-11-29
pubmed:abstractText
Protein tyrosine phosphatases from several microorganisms have been shown to play a role as virulence factors by modifying the phosphorylation/dephosphorylation equilibrium in cells of their host. Two tyrosine phosphatases, MptpA and MptpB, secreted by Mycobacterium tuberculosis, have been identified. Expression of MptpA is upregulated upon infection of monocytes, but its role in host cells has not been elucidated. A eukaryotic expression vector containing the mptpA cDNA has been transfected into macrophages. We report that MptpA reduced phagocytosis of mycobacteria, opsonized zymosan or zymosan, but had no effect on phagocytosis of IgG-coated particles. We also noted that the presence of F-actin at the surface of phagosomes containing opsonized zymosan was significantly increased in cells expressing MptpA. In the presence of recombinant MptpA, the process of actin polymerization at the surface of isolated phagosomes was increased; this was not the case in the presence of the phosphatase-dead mutant MptpA(C11S). MptpA had no effect when IgG-coated particles were present inside isolated phagosomes. These results indicate that, like other tyrosine phosphatases of pathogens, MptpA plays a role in phagocytosis and actin polymerization. However, MptpA had no effect on IgG particles, suggesting that its putative substrate(s) is not linked to the signaling pathways of Fcgamma receptors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0923-2508
pubmed:author
pubmed:issnType
Print
pubmed:volume
156
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1005-13
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Tyrosine phosphatase MptpA of Mycobacterium tuberculosis inhibits phagocytosis and increases actin polymerization in macrophages.
pubmed:affiliation
Institut de Pharmacologie et de Biologie Structurale, UMR CNRS 5089, 205 Route de Narbonne, 31077 Toulouse Cedex, France.
pubmed:publicationType
Journal Article