NRBP1
NRBP1 (nuclear receptor-binding protein 1) is an adaptor-type pseudokinase of the NRBP family: it binds nuclear receptors such as COUP-TFI (NR2F1) but lacks catalytic activity because of substitutions at key kinase motifs. Functionally, NRBP1 acts as a scaffold in ubiquitin-ligase complexes, participating in substrate-recognition assemblies that direct proteins such as SALL4 toward ubiquitin-mediated degradation. NRBP1 restrains cell proliferation and shows reduced expression in several cancers, behaving as a negative regulator of growth rather than a signaling kinase. Recombinant NRBP1 supports studies of pseudokinase scaffolds, nuclear-receptor interactions and ubiquitin-dependent protein turnover.
