IKK-induced NF-κB1 p105 proteolysis is critical for B cell antibody responses to T cell–dependent antigen

IKK-induced NF-κB1 p105 proteolysis is critical for B cell antibody responses to T cell–dependent antigen

The importance of IκB kinase (IKK)-induced proteolysis of NF-κB1 p105 in B cells was investigated using Nfkb1(SSAA/SSAA) mice, in which this NF-κB signaling pathway is blocked. Nfkb1(SSAA) mutation had no effect on the development and homeostasis of follicular mature (FM) B cells. However, analysis of mixed bone marrow chimeras revealed that Nfkb1(SSAA/SSAA) FM B cells were completely unable to...

Syk Tyrosine Kinase Is Critical for B Cell Antibody Responses and Memory B Cell Survival

Signals from the BCR are required for Ag-specific B cell recruitment into the immune response. Binding of Ag to the BCR induces phosphorylation of immune receptor tyrosine-based activation motifs in the cytoplasmic domains of the CD79a and CD79b signaling subunits, which subsequently bind and activate the Syk protein tyrosine kinase. Earlier work with the DT40 chicken B cell leukemia cell line ...

KPC1-Mediated Ubiquitination and Proteasomal Processing of NF-κB1 p105 to p50 Restricts Tumor Growth

NF-κB is a key transcriptional regulator involved in inflammation and cell proliferation, survival, and transformation. Several key steps in its activation are mediated by the ubiquitin (Ub) system. One uncharacterized step is limited proteasomal processing of the NF-κB1 precursor p105 to the p50 active subunit. Here, we identify KPC1 as the Ub ligase (E3) that binds to the ankyrin repeats doma...

TrCP-mediated proteolysis of NF-�B1 p105 requires phosphorylation of p105 serines 927

Lack of NF-κB1 (p105/p50) attenuates unloading-induced downregulation of PPARα and PPARα-regulated gene expression in rodent heart

Objective: Unloading of the rodent heart activates the fetal gene program, decreases peroxisome proliferator-activated receptor α (PPARα) and PPARα-regulated gene expression (MCAD), and induces cardiomyocyte atrophy. NF-κB regulates the fetal gene program and PPARαregulated gene expression during cardiac hypertrophy and induces atrophy in skeletal muscle. Our objective was to test the hypothesi...