Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.11.1 (
protein kinase
)
81,284
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The activity of purified RNA polymerase II from Novikoff ascites tumor cells is stimulated 5-7-fold by a purified protein factor. This protein factor, designated
HLF2
, has extensive
protein kinase
activity and catalyzed the incorporation of gamma-32G from ATP into protein under normal RNA polymerase assay conditions. Protein phosphorylation is totally dependent on the presence of
HLF2
and is stimulated 2-3-fold by the presence of highly purified RNA polymerase II. The purification procedure developed for the isolation of the polymerase stimulatory factor resulted in a 4000-fold purification of a
protein kinase
. Chromatography on carboxymethylcellulose, phosphocellulose, and Sephadex G-100 did not resolve polymerase stimulatory activity from
protein kinase
activity. Adenylimidodiphosphate (AMP-PNP), an inhibitor of protein kinases, inhibited the stimulatory activity of purified factor by 80%. The heat denaturation profile of
protein kinase
was paralleled by the loss of polymerase stimulatory activity. Concentrations of (NH4)2SO4 which are known to inhibit polymerase stimulation (Lee and Dahmus, 1973) also inhibit
protein kinase
activity. The
protein kinase
activity associated with stimulatory factor catalyzes the phosphorylation of basic proteins such as protamine or histone. The
protein kinase
is not stimulated by cyclic 3', 5'-AMP or -GMP over a concentration range of 10(-6)-10(-4)M. Furthermore,
protein kinase
activity is not inhibited by either the regulatory subunit of rabbit muscle protein kinase or by the heat-stable inhibitor of cyclic 3', 5'-AMP-dependent protein kinases. Protein kinase activity is stimulated by KCl or NH4Cl and is inhibited by MnCl2. The apparent Km values, determined in the presence of 4 mM Mg2+, are 0.02 mM for ATP, and 4.1 mM for GTP.
...
PMID:Stimulation of ascites tumor RNA polymerase II by protein kinase. 17 56
