Appearance of a novel plasma membrane phosphoprotein following culture of resting murine B lymphocytes with recombinant interleukin 4.
Culture of high density resting murine B cells with recombinant IL-4 caused changes in the patterns of phosphoproteins associated with the plasma membranes isolated from such cells. The principal difference was the appearance of an alkali-resistant phosphoprotein of Mr = 75,000-80,000. Culture with LPS also gave rise to a characteristic alteration in phosphoprotein profiles, but this was distinct from the cytokine-induced changes and did not include induction of a 75 kDa signal. Culture in medium plus serum only failed to produce an alteration of the phosphoprotein profile of membranes isolated from B cells cultured in this manner. Culture of high density murine splenic B cells with IL-4 in the presence of the 11B11 anti-IL-4 monoclonal antibody prevented the appearance of the 75 kDa phosphoprotein, indicating that IL-4 binding was necessary for induction of the 75 kDa phosphoprotein signal. The possible molecular identity of the 75 kDa phosphoprotein and its role in control of B lymphocyte differentiation is discussed.
McGarvie
G M
GM
Department of Biochemistry, University of Glasgow, Scotland, U.K.
Cushley
W
W
D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D015847:Interleukin-4 / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008565:Membrane Proteins / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D008970:Molecular Weight; D010750:Phosphoproteins / Q000096:biosynthesis*; D010766:Phosphorylation; D011994:Recombinant Proteins; D013154:Spleen / Q000166:cytology
D008070:Lipopolysaccharides; D008565:Membrane Proteins; D010750:Phosphoproteins; D011994:Recombinant Proteins; D015847:Interleukin-4