title: Counterregulation by the coreceptors CD19 and CD22 of MAP kinase activation by membrane immunoglobulin.
abstract: The signaling pathways linked to membrane immunoglobulin (mIg) that are regulated by the coreceptors CD19 and CD22 are not known. The mitogen-activated protein (MAP) kinases ERK2, JNK, and p38 couple extracellular signals to transcriptional responses. The capacity of mIg to activate these MAP kinases is synergistically amplified by coligating CD19, and this effect requires that CD19 be juxtaposed to mIg. CD22 suppresses MAP kinase activation when cross-linked to mIg alone or to the coligated complex of mIg and CD19. Separate ligation and sequestration of CD22 from mIg enhances MAP kinase activation, probably reflecting release of mIg from constitutive down-regulation. Thus, CD19 and CD22 have counterregulatory effects on MAP kinase activation by mIg, which are dependent on their proximity to the antigen receptor.
authors.affiliation: Department of Medicine, University of Cambridge School of Clinical Medicine, United Kingdom.
authors.forename: R M
authors.initials: RM
authors.lastname: Tooze
authors.forename: G M
authors.initials: GM
authors.lastname: Doody
authors.forename: D T
authors.initials: DT
authors.lastname: Fearon
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D018941:Antigens, CD19 / Q000378:metabolism*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000378:metabolism*; D001402:B-Lymphocytes / Q000201:enzymology* / Q000276:immunology; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D004789:Enzyme Activation; D048031:JNK Mitogen-Activated Protein Kinases; D037102:Lectins; D051379:Mice; D008807:Mice, Inbred BALB C; D019950:Mitogen-Activated Protein Kinase 1; D020928:Mitogen-Activated Protein Kinases; D011485:Protein Binding; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011947:Receptors, Antigen, B-Cell / Q000378:metabolism*; D051918:Sialic Acid Binding Ig-like Lectin 2; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D015703:Antigens, CD; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte; C497868:Cd22 protein, mouse; D015815:Cell Adhesion Molecules; D037102:Lectins; D011947:Receptors, Antigen, B-Cell; D051918:Sialic Acid Binding Ig-like Lectin 2; D011505:Protein-Tyrosine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases