Protein kinase activity associated with Fc. gamma. /sub 2a/ receptor of a murine macrophage like cell line, P388D/sub 1/

Journal Article · Tue Dec 15 04:00:00 EST 1987 · Biochemistry; (United States)

OSTI ID:5438153

Hirata, Y; Suzuki, T

The properties of protein kinase activity associated with Fc receptor specific for IgG/sub 2a/(Fc..gamma../sub 2a/R) of a murine macrophage like cell line, P388D/sub 1/, were investigated. IgG/sub 2a/-binding protein isolated from the detergent lysate of P388D/sub 1/ cells by affinity chromatography of IgG-Sepharose was found to contain four distinct proteins of M/sub r/ 50,000, 43,000, 37,000, and 17,000, which could be autophosphorylated upon incubation with (..gamma..-/sup 32/P)ATP. The autophosphorylation of Fc..gamma../sub 2a/ receptor complex ceased when exogenous phosphate acceptors (casein or histone) were added in the reaction mixture. Phosphorylation of casein catalyzed by Fc..gamma../sub 2a/ receptor complex was dependent on casein concentration, increased with time or temperature, was dependent on the concentration of ATP and Mg/sup 2 +/, and was maximum at pH near 8. Casein phosphorylation was significantly inhibited by a high concentration of Mn/sup 2 +/ or KCl or by a small amount of heparin and was enhanced about 2-fold by protamine. Casein kinase activity associated with Fc..gamma../sub 2a/ receptor used ATP as substrate with an apparent K/sub m/ of 2 ..mu..M as well as GTP with an apparent K/sub m/ of 10 ..mu..M. Prior heating (60/sup 0/C for 15 min) or treatment with protease (trypsin or Pronase) of Fc..gamma../sub 2a/ receptor complex almost totally abolished casein kinase activity. Thin-layer chromatography of a partial acid hydrolysate of the phosphorylated casein showed that the site of phosphorylation is at a seryl residue. These results suggest that Fc..gamma../sub 2//sub a/ receptor forms a molecule complex with protein kinase, whose characteristics resemble those of type II casein kinase but are different from those of cyclic nucleotide dependent protein kinase or from those of C protein kinase.

• Research Organization: Univ. of Kansas Medical Center, Kansas City
• OSTI ID: 5438153
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 26:25; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANIMALS
ATP
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
CARBON 14 COMPOUNDS
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
ENZYME ACTIVITY
ENZYMES
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LIGHT NUCLEI
MACROPHAGES
MAMMALS
MEMBRANE PROTEINS
MICE
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PHAGOCYTES
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
RODENTS
SOMATIC CELLS
TRANSFERASES
VERTEBRATES