A beta integrin subunit regulates bacterial phagocytosis in medfly haemocytes.
We have recently reported that the activation of focal adhesion kinase (FAK) and its downstream targets upon pathogen challenge regulate phagocytosis in medfly haemocytes. The goal of this study was to further explore the signalling pathway underlying the process of phagocytosis. In particular, in this report, we used flow cytometry, RNA interference, enzyme-linked immunosorbent assay, Western blot and immunoprecipitation analysis to demonstrate the haemocyte surface receptor, through which the extracellular signals in response to bacteria are transmitted intracellularly. The presented data demonstrate the expression of a beta integrin subunit in the surface of medfly haemocytes that transmits signals upon pathogen triggering to FAK and its downstream targets, Src, MAP kinases and Elk-1-like protein, for the engulfment of pathogen. Interestingly LPS is not internalized through integrins.
Mamali
Irene
I
Department of Biology, University of Patras, Patras, Greece.
Lamprou
Irene
I
Karagiannis
Fotis
F
Karakantza
Marina
M
Lampropoulou
Maria
M
Marmaras
Vassilis J
VJ
D000818:Animals; D033622:Ceratitis capitata / Q000276:immunology* / Q000382:microbiology*; D004926:Escherichia coli / Q000276:immunology; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism; D006434:Hemocytes / Q000276:immunology* / Q000382:microbiology*; D039641:Integrin beta Chains / Q000096:biosynthesis*; D020928:Mitogen-Activated Protein Kinases / Q000276:immunology / Q000378:metabolism; D010587:Phagocytosis; D015398:Signal Transduction / Q000276:immunology; D013211:Staphylococcus aureus / Q000276:immunology; D050807:ets-Domain Protein Elk-1 / Q000276:immunology / Q000378:metabolism; D019061:src-Family Kinases / Q000276:immunology / Q000378:metabolism
D039641:Integrin beta Chains; D050807:ets-Domain Protein Elk-1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D019061:src-Family Kinases; D020928:Mitogen-Activated Protein Kinases