Regulation of phosphorylation of nicotinic acetylcholine receptors in mouse BC3H1 myocytes

Journal Article · Tue Sep 01 00:00:00 EDT 1987 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.84.18.6601· OSTI ID:7253427

Smith, M M; Merlie, J P; Lawrence, Jr, J C

By using /sup 32/P-labeling methods and performing immunoprecipitations with specific antibodies, the authors have found that three subunits of the nicotinic acetylcholine receptor and phosphorylated in mouse skeletal muscle cells. In nonstimulated cells, the molar ratios of phosphate estimated in ..cap alpha.., ..beta.., and delta subunits were 0.02, 0.05, and 0.5, respectively. All three subunits contained predominantly phosphoserine with some phosphothreonine; the ..beta.., subunit also contained phosphotyrosine. Incubating cells with agents that stimulate cAMP-dependent pathways (isoproterenol, forskolin, 8-Br-cAMP) increased the phosphorylation of the delta subunit by 50%, but phosphate labeling of the ..beta.. subunit was depressed by a third. In contrast, when cells were incubated with the divalent cation ionophores A-23187 or ionomycin, phosphorylation of both the delta and ..beta.. subunits increased. The results indicate that acetylcholine receptors are phosphorylated to significant levels in skeletal muscle cells and that cAMP-dependent and Ca/sup 2 +/-dependent pathways exist for controlling the phosphorylation state of the receptor subunits.

• Research Organization: Washington Univ. School of Medicine, St. Louis, MO (USA)
• OSTI ID: 7253427
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Journal Name: Proc. Natl. Acad. Sci. U.S.A.; (United States) Vol. 84:18; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
ALKALINE EARTH METAL COMPOUNDS
AMINES
AMMONIUM COMPOUNDS
AMP
ANTIGENS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL PATHWAYS
CALCIUM COMPOUNDS
CATIONS
CELL CULTURES
CHARGED PARTICLES
CHEMICAL REACTIONS
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ESTERS
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
IONS
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MATERIALS
MEMBRANE PROTEINS
MUSCLES
NEUROREGULATORS
NUCLEI
NUCLEOTIDES
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PARASYMPATHOMIMETICS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PHOSPHORYLATION
PROTEINS
QUATERNARY COMPOUNDS
RADIOISOTOPES
RADIORECEPTOR ASSAY
RECEPTORS
TOXIC MATERIALS
TOXINS
TRACER TECHNIQUES