title: Involvement of signal transduction pathways in Salmonella typhimurium porin activated gut macrophages.
abstract: Many membrane proteins are implicated in the regulation of cell functions by triggering specific signaling pathways. Porins are known potential modulators of cell proliferation and differentiation. We explored the possible involvement of this protein in signal transduction pathways in mouse gut macrophages. In the present work we have shown that porins can trigger signal transduction in mouse macrophages infected with S. typhimurium. Activation of macrophages by porins results in an increase in inositol trisphosphate and intracellular Ca2+ mobilization. There is a translocation of protein kinase C to the membrane which is accompanied by nitric oxide release within the macrophages. This effect is the outcome of the expression of nitric oxide synthase, which is dependent on Protein kinase C. Further, we observed that there is an increased binding of the porins on macrophages infected with S. typhimurium which results in activation of macrophages and triggering of specific signaling pathways. These results indicate that porins induce the production of nitric oxide via a protein kinase C dependent pathway. Nitric oxide plays a fundamental role in macrophage effector function where it has both communication and defensive function.
authors.affiliation: Division of Cardiology 111 C, V.A. Medical Center, Minneapolis, MN, USA.
authors.forename: S
authors.initials: S
authors.lastname: Gupta
authors.forename: D
authors.initials: D
authors.lastname: Kumar
authors.forename: H
authors.initials: H
authors.lastname: Vohra
authors.forename: N K
authors.initials: NK
authors.lastname: Ganguly
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D002118:Calcium / Q000378:metabolism; D008262:Macrophage Activation; D008264:Macrophages / Q000201:enzymology / Q000378:metabolism / Q000382:microbiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000096:biosynthesis; D019001:Nitric Oxide Synthase / Q000378:metabolism; D018272:Porins / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism; D012486:Salmonella typhimurium / Q000276:immunology / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D000942:Antigens, Bacterial; D018272:Porins; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D011493:Protein Kinase C; D002118:Calcium