title: The molecular mechanism of B cell activation by toll-like receptor protein RP-105.
abstract: The B cell-specific transmembrane protein RP-105 belongs to the family of Drosophila toll-like proteins which are likely to trigger innate immune responses in mice and man. Here we demonstrate that the Src-family protein tyrosine kinase Lyn, protein kinase C beta I/II (PKCbetaI/II), and Erk2-specific mitogen-activated protein (MAP) kinase kinase (MEK) are essential and probably functionally connected elements of the RP-105-mediated signaling cascade in B cells. We also find that negative regulation of RP-105-mediated activation of MAP kinases by membrane immunoglobulin may account for the phenomenon of antigen receptor-mediated arrest of RP-105-mediated B cell proliferation.
authors.affiliation: Department of Laboratory Medicine, University of California, San Francisco, California 94143, USA.
authors.forename: V W
authors.initials: VW
authors.lastname: Chan
authors.forename: I
authors.initials: I
authors.lastname: Mecklenbräuker
authors.forename: I
authors.initials: I
authors.lastname: Su
authors.forename: G
authors.initials: G
authors.lastname: Texido
authors.forename: M
authors.initials: M
authors.lastname: Leitges
authors.forename: R
authors.initials: R
authors.lastname: Carsetti
authors.forename: C A
authors.initials: CA
authors.lastname: Lowell
authors.forename: K
authors.initials: K
authors.lastname: Rajewsky
authors.forename: K
authors.initials: K
authors.lastname: Miyake
authors.forename: A
authors.initials: A
authors.lastname: Tarakhovsky
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D029721:Drosophila Proteins; D004789:Enzyme Activation / Q000276:immunology; D005434:Flow Cytometry; D007075:Immunoglobulin M / Q000276:immunology; D008562:Membrane Glycoproteins / Q000276:immunology / Q000502:physiology*; D008565:Membrane Proteins / Q000276:immunology; D051379:Mice; D018345:Mice, Knockout; D020929:Mitogen-Activated Protein Kinase Kinases; D010766:Phosphorylation; D011493:Protein Kinase C / Q000502:physiology; D011494:Protein Kinases / Q000502:physiology; D011956:Receptors, Cell Surface / Q000276:immunology / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology; D013154:Spleen / Q000276:immunology; D051193:Toll-Like Receptors; D019061:src-Family Kinases / Q000502:physiology
chemical_list: D029721:Drosophila Proteins; D007075:Immunoglobulin M; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D051193:Toll-Like Receptors; D011494:Protein Kinases; D019061:src-Family Kinases; D011493:Protein Kinase C; D020929:Mitogen-Activated Protein Kinase Kinases; D002118:Calcium