PRKCB1 Protein, Human (Active, sf9, GST)

PKC beta 1 is a calcium-activated, phospholipid- and diacylglycerol (DAG)-dependent serine/threonine-protein kinase involved in various cellular processes, including regulation of the B-cell receptor (BCR) signalosome, oxidative stress-induced apoptosis, androgen receptor-dependent transcription regulation, insulin signaling, and endothelial cell proliferation. It plays a key role in B-cell activation by regulating BCR-induced NF-kappa-B activation. PKC beta 1 mediates the activation of the canonical NF-kappa-B pathway (NFKB1) by directly phosphorylating CARD11/CARMA1 at 'Ser-559', 'Ser-644', and 'Ser-652'. Additionally, it negatively regulates BCR signaling by phosphorylating BTK at 'Ser-180', inhibiting BTK activity. In apoptosis following oxidative damage, PKC beta 1 specifically phosphorylates 'Ser-36' of the p66Shc isoform of SHC1, leading to mitochondrial accumulation of p66Shc and reactive oxygen species production. As a coactivator of androgen receptor (AR)-dependent transcription, PKC beta 1 is recruited to AR target genes and phosphorylates histone H3 at 'Thr-6' (H3T6ph), preventing demethylation of histone H3 'Lys-4' (H3K4me) by LSD1/KDM1A. In insulin signaling, PKC beta 1 may function downstream of IRS1 and mediate insulin-dependent DNA synthesis through the RAF1-MAPK/ERK cascade. It also negatively modulates insulin-stimulated translocation of the glucose transporter SLC2A4/GLUT4 in adipocytes. PKC beta 1 phosphorylates SLC2A1/GLUT1, promoting glucose uptake. Under high glucose conditions, it likely inhibits insulin gene transcription in pancreatic beta-cells via regulation of MYC expression. In endothelial cells, PKC beta 1 activation increases RB1 phosphorylation, enhances VEGFA-induced proliferation, and inhibits PI3K/AKT-dependent nitric oxide synthase (NOS3/eNOS) regulation, contributing to endothelial dysfunction. PKC beta 1 is also involved in triglyceride homeostasis (by similar). It phosphorylates ATF2, promoting ATF2-JUN cooperation and transcriptional activation. In angiotensin II signaling, PKC beta 1 phosphorylates KLHL3, reducing its interaction with WNK4. Additionally, it phosphorylates and activates LRRK1, which in turn phosphorylates RAB proteins involved in intracellular trafficking.