umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Disruption of target cell adhesion structures by the Yersinia effector YopH requires interaction with the substrate domain of p130Cas.
Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). (Fällman)
Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). (Fällman)
Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). (Fällman)
Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). (Fällman)
Show others and affiliations
2005 (English)In: European Journal of Cell Biology, ISSN 0171-9335, E-ISSN 1618-1298, Vol. 84, no 4, 477-489 p.Article in journal (Refereed) Published
Abstract [en]

The docking protein p130Cas has, together with FAK, been found as a target of the Yersinia virulence effector YopH. YopH is a protein tyrosine phosphatase that is delivered into host cells via the bacterial type III secretion machinery, and the outcome of its activity is inhibition of host cell phagocytosis. In the present study using p130Cas-/- cells, and p130Cas-/- cells expressing variants of GFPp130Cas, we show that this docking protein, via its substrate domain, is responsible for subcellular targeting of YopH in eukaryotic cells. Since YopH inhibits phagocytosis, p130Cas was expected to be critical for signalling mediating bacterial internalization. However, p130Cas-/- cells did not exhibit reduced capacity to internalize Yersinia. On the other hand, when a dominant negative variant of p130Cas was expressed in these cells, the phagocytic capacity was severely impaired. Moreover, the p130Cas-/- cells displayed a marked reduced sensitivity towards YopH-mediated detachment compared to wild-type cells. Transfecting these cells with full-length p130Cas rendered cells hypersensitive to both mechanical and Yersinia-mediated detachment. This hypersensitivity was not seen upon transfection with the dominant negative substrate domain-deleted variant of p130Cas. This implicates p130Cas as a prominent regulator of cell adhesion, where its substrate-binding domain has a significant function.The docking protein p130Cas has, together with FAK, been found as a target of the Yersinia virulence effector YopH. YopH is a protein tyrosine phosphatase that is delivered into host cells via the bacterial type III secretion machinery, and the outcome of its activity is inhibition of host cell phagocytosis. In the present study using p130Cas-/- cells, and p130Cas-/- cells expressing variants of GFPp130Cas, we show that this docking protein, via its substrate domain, is responsible for subcellular targeting of YopH in eukaryotic cells. Since YopH inhibits phagocytosis, p130Cas was expected to be critical for signalling mediating bacterial internalization. However, p130Cas-/- cells did not exhibit reduced capacity to internalize Yersinia. On the other hand, when a dominant negative variant of p130Cas was expressed in these cells, the phagocytic capacity was severely impaired. Moreover, the p130Cas-/- cells displayed a marked reduced sensitivity towards YopH-mediated detachment compared to wild-type cells. Transfecting these cells with full-length p130Cas rendered cells hypersensitive to both mechanical and Yersinia-mediated detachment. This hypersensitivity was not seen upon transfection with the dominant negative substrate domain-deleted variant of p130Cas. This implicates p130Cas as a prominent regulator of cell adhesion, where its substrate-binding domain has a significant function.

Place, publisher, year, edition, pages
2005. Vol. 84, no 4, 477-489 p.
Keyword [en]
Animals, Bacterial Outer Membrane Proteins/*physiology, Cell Adhesion, Crk-Associated Substrate Protein, Fibroblasts/cytology/metabolism/microbiology, Focal Adhesion Kinase 1, Focal Adhesion Protein-Tyrosine Kinases, Focal Adhesions, Mice, Phagocytosis, Protein Binding, Protein Structure; Tertiary, Protein-Tyrosine Kinases/metabolism, Protein-Tyrosine-Phosphatase/*physiology, Proteins/genetics/*physiology, Retinoblastoma-Like Protein p130, Virulence, Yersinia/*pathogenicity
National Category
Medical and Health Sciences
Identifiers
URN: urn:nbn:se:umu:diva-16647DOI: 10.1016/j.ejcb.2004.11.009PubMedID: 15900707OAI: oai:DiVA.org:umu-16647DiVA: diva2:156320
Available from: 2007-10-08 Created: 2007-10-08 Last updated: 2017-12-14Bibliographically approved
In thesis
1. Antiphagocytosis by Yersinia pseudotuberculosis: role of the YopH target proteins
Open this publication in new window or tab >>Antiphagocytosis by Yersinia pseudotuberculosis: role of the YopH target proteins
2006 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The enteropathogenic bacterium Yersinia pseudotuberculosis binds to β1 integrins on a host cell via its surface protein invasin. This event stimulates signal transduction to the actin cytoskeleton of the eukaryotic cell, which allows the cell to engulf the bacterium that is attached to its surface. However, the pathogen Y. pseudotuberculosis can evade such phagocytosis by injecting virulence effectors that interfere with the antipathogenic machinery of the host cells. One of these virulence effectors is the tyrosine phosphatase YopH. Through its enzymatic activity, YopH blocks phagocytosis by affecting the signalling that is associated with cytoskeletal rearrangements.

Cas is a substrate of YopH in both professional and non-professional phagocytes. We showed that YopH binds to the central substrate domain of Cas and that this interaction is required for YopH to target focal adhesion structures in host cells. We also demonstrated that YopH binds another substrate, FAK, through Cas. Moreover, we suggested that targeting of Cas is necessary for the cytotoxic effects mediated by YopH.

The protein Fyb is specific to immune cells, and it has been identified as a substrate of YopH in macrophages. We discovered that both the N-terminal substrate-binding domain and the C-terminal catalytic region of YopH bind Fyb in a phosphotyrosine-dependent manner. Moreover, we observed that both the substrate-binding domain and the phosphatase activity of YopH are essential for the effects of this protein on macrophages, which include dephosphorylation of Fyb, blocking of phagocytosis, and cytotoxicity.

The role of Fyb in macrophages is largely unknown, although there is evidence that this protein is involved in integrin-linked actin organization. We identified a novel interaction partner of Fyb, mAbp1, which is a protein that binds to F-actin. Studies in vitro indicated that mAbp1 binds to the N terminus of Fyb via a C-terminal SH3 domain. We also found that both Fyb and mAbp1 co-localize with F-actin at the leading edges of macrophages. Further studies suggested that mAbp1 influences the spreading of macrophages and the antiphagocytosis mediated by pathogenic Yersinia. These results support a role for Fyb in signalling that affects F-actin dynamics, and they also provide additional insight into the mechanisms involved. Fyb has been shown to form a complex with SKAP-HOM, another substrate of YopH in macrophages. Our data implied that the level of SKAP-HOM protein depends on the presence of Fyb, but the function of the Fyb/SKAP-HOM complex in macrophages has not been determined. However, since Fyb is the only known haematopoietic-specific substrate of YopH, it is possible that Fyb is involved in other antimicrobial functions.

Place, publisher, year, edition, pages
Umeå: Molekylärbiologi, 2006. 65 p.
Series
Doctoral thesis / Umeå University, Department of Molecular Biology, 1072
Keyword
Molecular biology, Cas, Fyb, mAbp1, SKAP-HOM, Yersinia pseudotuberculosis, YopH, Molekylärbiologi
Research subject
Molecular Biology
Identifiers
urn:nbn:se:umu:diva-957 (URN)91-7264-219-X (ISBN)
Public defence
2007-02-01, Major Groove, NUS, 6L, Department of Molecular Biology, Umea University, Umea, 09:00 (English)
Opponent
Supervisors
Available from: 2006-12-21 Created: 2006-12-21 Last updated: 2009-10-30Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMedhttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Retrieve&list_uids=15900707&dopt=Citation

Search in DiVA

By author/editor
Fällman, Maria
By organisation
Department of Molecular Biology (Faculty of Medicine)Umeå Centre for Microbial Research (UCMR)
In the same journal
European Journal of Cell Biology
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 95 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf