I₂^PP2A
Protein Phosphatase 2A Inhibitor I

Liquid. In 50 mM Tris-HCl, 14 mM bME, 1 mM benzamidine, 1 mM EDTA, 0.1 mM PMSF, 10% glycerol, pH 7.4. AVOID FREEZE/THAW CYCLES. Recombinant, human PP2AI I₂ fused to GST and expressed in E. coli. Inhibits protein phosphatase 2A (PP2A) potently with K_i ~ 25-30 nM with myelin basic protein, histone H1, and other substrates of PP2A but not with casein as a substrate. Stimulates PP1. Prevents inhibition of E-Cdk-2 by p21^Cip1. Associates with B cyclin. Regulates histone binding to DNA, transcriptional activity and chromatin condensation. Undergoes phosphorylation in cells. Highly expressed in some cancers. Associates with HRX leukemia-associated fusion proteins. Occurs as fusion protein in acute undifferentiated leukemia. Does not inhibit PP1, PP2B, PP2C, or pyruvate dehydrogenase. Purity: ≥90% by SDS-PAGE.

Ref.: Li, M., et al. 1996. Biochemistry 35, 6998. Li, M., et al. 1995. Biochemistry 34, 1988.