Biomaterial Database

Change in state of phosphorylation of acetylcholine receptor during maturation of the electromotor synapse in Torpedo marmorata electric organ. 1981

T Saitoh, and J P Changeux

Two populations of membrane fragments, both rich in acetylcholine receptor (AcChoR), appeared during subcellular fractionation by ultracentrifugation of neonatal Torpedo marmorata electric organs. One of these equilibrated at 38.5% (wt/wt) sucrose, as did AcChoR-rich membranes from adult fish; the other equilibrated at 36.8% sucrose. AcChoR purified from these light membrane fractions gave the same subunit profile as adult AcChoR (after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate) but was more susceptible to heat inactivation and focused at an isoelectric point more alkaline by 0.1 pH unit. Treatment of adult AcChoR with Escherichia coli alkaline phosphatase decreased its thermal stability and shifted its isoelectric point towards alkaline pH. However, identical treatment did not affect AcChoR purified from neonatal light membrane fractions. The gamma and delta chains of AcChoR can be phosphorylated in vitro by endogenous protein kinases, which copurify with AcChoR-rich membranes. Treatment of AcChoR from neonatal light membranes by E. coli alkaline phosphatase enhanced the phosphorylation of the gamma and delta chains but did so to a smaller extent than in the case of adult AcChoR. In conclusion, adult AcChoR appears to be more phosphorylated than AcChoR from neonatal light membranes, indicating that its state of phosphorylation changes during development.

UI	MeSH Term	Description	Entries
D007526	Isoelectric Point	The pH in solutions of proteins and related compounds at which the dipolar ions are at a maximum.	Isoelectric Points,Point, Isoelectric,Points, Isoelectric
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D011950	Receptors, Cholinergic	Cell surface proteins that bind acetylcholine with high affinity and trigger intracellular changes influencing the behavior of cells. Cholinergic receptors are divided into two major classes, muscarinic and nicotinic, based originally on their affinity for nicotine and muscarine. Each group is further subdivided based on pharmacology, location, mode of action, and/or molecular biology.	ACh Receptor,Acetylcholine Receptor,Acetylcholine Receptors,Cholinergic Receptor,Cholinergic Receptors,Cholinoceptive Sites,Cholinoceptor,Cholinoceptors,Receptors, Acetylcholine,ACh Receptors,Receptors, ACh,Receptor, ACh,Receptor, Acetylcholine,Receptor, Cholinergic,Sites, Cholinoceptive
D004557	Electric Organ	In about 250 species of electric fishes, modified muscle fibers forming disklike multinucleate plates arranged in stacks like batteries in series and embedded in a gelatinous matrix. A large torpedo ray may have half a million plates. Muscles in different parts of the body may be modified, i.e., the trunk and tail in the electric eel, the hyobranchial apparatus in the electric ray, and extrinsic eye muscles in the stargazers. Powerful electric organs emit pulses in brief bursts several times a second. They serve to stun prey and ward off predators. A large torpedo ray can produce of shock of more than 200 volts, capable of stunning a human. (Storer et al., General Zoology, 6th ed, p672)	Electric Organs,Organ, Electric,Organs, Electric
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D000469	Alkaline Phosphatase	An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.1.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014101	Torpedo	A genus of the Torpedinidae family consisting of several species. Members of this family have powerful electric organs and are commonly called electric rays.	Electric Rays,Torpedinidae,Rays, Electric
D046911	Macromolecular Substances	Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.	Macromolecular Complexes,Macromolecular Compounds,Macromolecular Compounds and Complexes,Complexes, Macromolecular,Compounds, Macromolecular,Substances, Macromolecular