Hemese, a hemocyte-specific transmembrane protein, affects the cellular immune response in Drosophila.
2003 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 100, no 5, 2622-7 p.Article in journal (Refereed) Published
We have identified a previously undescribed transmembrane protein, Hemese, from Drosophila melanogaster blood cells (hemocytes), by using a monoclonal pan-hemocyte antibody. Heavy glycosylation is suggested by the heterogeneous size distribution, ranging between 37 and 70 kDa. Hemese expression is restricted to the cell surfaces of hemocytes of all classes, and to the hematopoietic organs. The sequence of the corresponding gene, Hemese (He), predicts a glycophorin-like protein of 15 kDa, excluding an N-terminal signal peptide, with a single hydrophobic transmembrane region. The extracellular region consists mainly of Ser/Thr-rich sequence of low complexity, with several potential O-glycosylation sites. Hemese contains phosphotyrosine and the cytoplasmic region has potential phosphorylation sites, suggesting an involvement in signal transduction. Depletion of Hemese by RNA interference has no obvious effect under normal conditions, but the cellular response to parasitic wasps is much enhanced. This finding indicates that Hemese plays a modulatory role in the activation or recruitment of the hemocytes.
Place, publisher, year, edition, pages
2003. Vol. 100, no 5, 2622-7 p.
Amino Acid Sequence, Animals, Blotting; Western, Cell Membrane/*metabolism, Cell Separation, Cloning; Molecular, Cytoplasm/metabolism, DNA; Complementary/metabolism, Drosophila, Drosophila Proteins/*chemistry/*physiology, Flow Cytometry, Gene Library, Glycosylation, Green Fluorescent Proteins, Hemocytes/*metabolism, Hybridomas, Immunohistochemistry, Luminescent Proteins/metabolism, Membrane Proteins/*chemistry/*physiology, Molecular Sequence Data, Peptides/chemistry, Phagocytosis, Phosphorylation, Precipitin Tests, Protein Structure; Tertiary, RNA/metabolism, RNA Interference, Signal Transduction, Tyrosine/metabolism
IdentifiersURN: urn:nbn:se:umu:diva-17060DOI: 10.1073/pnas.0436940100PubMedID: 12598653OAI: oai:DiVA.org:umu-17060DiVA: diva2:156733