Uptake and intracellular transportation of a bacterial surface protein in lymphoid cells.
Author
Summary, in English
Some strains of the human pathogen Streptococcus pyogenes express a surface protein called protein H, which is released from the streptococcal surface by a cysteine proteinase produced by the bacteria. Here, we find that soluble protein H binds to the surface of lymphocytes and granulocytes, and that the molecule is taken up by lymphocytes and transported to the perinuclear region. The translocation over the cell membrane is rapid, and the uptake and intracellular transportation is not dependent on actin polymerization. Protein H could be immunoprecipitated from cell extracts and nuclear preparations of lymphocytes, and analysis of molecular interactions between pro-tein H and proteins of different cellular compart-ments demonstrated a binding to nucleophosmin/ B23, a protein known to shuttle between the cytoplasm and the nucleus, and to the nuclear proteins SET and hnRNP A2/B1. Nucleophosmin/B23 was co-immunoprecipitated with protein H from cell and nuclear extracts, and binding experiments, including kinetic analyses, suggest that protein H dissociating from nucleophosmin/B23 complexes in the perinuclear region or in the nucleus binds to proteins SET and hnRNP A2/B1. Finally, the uptake and intracellular transportation of protein H was found to result in a cytostatic effect on B and T lymphocytes.
Department/s
Publishing year
2002
Language
English
Pages
917-934
Publication/Series
Molecular Microbiology
Volume
44
Issue
4
Links
Document type
Journal article
Publisher
Wiley-Blackwell
Topic
- Infectious Medicine
Status
Published
Research group
- Immunology
ISBN/ISSN/Other
- ISSN: 1365-2958