Inhibitory effect of c-fos overexpression on B cell proliferative responses to membrane IGM cross-linking.
Constitutive expression of the c-fos gene perturbs the de novo synthesis of RNA and DNA in B cells stimulated by surface immunoglobulin (sIg) cross-linking. In order to examine kinetics of the regulatory effect on the activation process of B cells, we used splenic B cells from transgenic mice carrying the c-fos gene under the control of the interferon alpha/beta (IFN)-inducible Mx gene promoter (Mx-c-fos). In the absence of IFN, Mx-c-fos B cells proliferated well by anti-IgM stimulation. However, both RNA and DNA synthesis in the Mx-c-fos B cells were markedly reduced by the addition of IFN in the culture within 12 h after anti-IgM stimulation. These results suggest that this regulatory effect of c-Fos displays at the mid G1 phase of the cell cycle.
Tomita
Y
Y
Department of Orthopedic Surgery, Kobe University School of Medicine.
Koizumi
T
T
Mizuno
K
K
Tokuhisa
T
T
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D001483:Base Sequence; D019204:GTP-Binding Proteins; D005786:Gene Expression Regulation / Q000187:drug effects; D016762:Genes, fos; D007075:Immunoglobulin M / Q000276:immunology*; D007152:Immunologic Capping; D016898:Interferon-alpha / Q000494:pharmacology; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D064547:Myxovirus Resistance Proteins; D011401:Promoter Regions, Genetic / Q000187:drug effects; D011506:Proteins / Q000235:genetics; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis*; D013154:Spleen / Q000166:cytology
D007075:Immunoglobulin M; D016898:Interferon-alpha; C579070:Mx1 protein, mouse; D064547:Myxovirus Resistance Proteins; D011506:Proteins; D016760:Proto-Oncogene Proteins c-fos; D011993:Recombinant Fusion Proteins; D019204:GTP-Binding Proteins