Qualitative changes in the subunit composition of kappa B-binding complexes during murine B-cell differentiation.
We report here that the major kappa B-binding complex in murine mature B cells is composed of a p50-Rel heterodimer, whereas the major inducible form in pre-B cells is a p50-p65 heterodimer. Treatment of a pre-B-cell line with lipopolysaccharide changes the subunit composition of kappa B-binding complexes from p50-p65 to p50-Rel. This change is preceded by the enhanced Rel expression and correlates with the expression of the gene for the immunoglobin kappa light chain. The heterodimeric p50-Rel complex binds to the intronic enhancer-kappa B site in the immunoglobulin kappa light chain gene at least 20-fold more stably than does the p50-p65 dimer. These data support a model in which augmentation of Rel expression during the differentiation of pre-B cells to mature B cells leads to an exchange of kappa B-binding subunits resulting in the transcriptional activation of the gene for the immunoglobulin kappa light chain.
Miyamoto
S
S
Molecular Biology and Virology Laboratory, Salk Institute, San Diego, CA 92186-5800.
Schmitt
M J
MJ
Verma
I M
IM
D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology* / Q000378:metabolism; D001483:Base Sequence; D002454:Cell Differentiation; D002460:Cell Line; D004247:DNA; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000378:metabolism*; D052002:NF-kappa B p50 Subunit; D011485:Protein Binding; D051996:Transcription Factor RelA
D008070:Lipopolysaccharides; D016328:NF-kappa B; D052002:NF-kappa B p50 Subunit; D051996:Transcription Factor RelA; D004247:DNA