Effects of polyamine hydrochlorides on dephosphorylation of phosphorylated H2B histone integrated into nucleosome core particles.
The rate of dephosphorylation of isolated P-H2B histone by pig heart phosphoprotein phosphatase (Mr = 224,000) and its catalytic subunit (Mr = 31,000) was suppressed more than 95% at low ionic strength when the substrate was integrated into nucleosome core particles. The suppressed rate was increased 13-43-fold by polyamine hydrochlorides and Mg(CH3COO)2 at the optimal ionic strength of 0.2-0.38 M. Phosphatase activity toward integrated P-H2B histone was distributed in both rat liver cytosol and nuclear extracts. The phosphatase activities in these fractions showed similar specific activities and were also increased 10-32-fold by 10 mM spermine.4HCl.
D000818:Animals; D003600:Cytosol / Q000378:metabolism; D006657:Histones / Q000378:metabolism*; D009206:Myocardium / Q000201:enzymology; D009707:Nucleosomes / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D011073:Polyamines / Q000494:pharmacology*; D013552:Swine
D006657:Histones; D009707:Nucleosomes; D010750:Phosphoproteins; D011073:Polyamines; D010749:Phosphoprotein Phosphatases