Isolation and characterization of nicotinic acetylcholine receptor-like protein from fetal calf thymus.
A nicotinic acetylcholine receptor-like protein (AChR-LP) was isolated from fetal calf thymus by affinity chromatography using cobrotoxin-Sepharose after alkaline extraction and solubilization with Triton X-100. The AChR-LP had a specificity of 1.61 +/- 1.12 nmol of alpha-bungarotoxin binding sites per mg of protein. The isoelectric point, sedimentation coefficient and amino acid composition of the purified AChR-LP were very similar to those of muscle and electric organ AChRs. Upon SDS-polyacrylamide gel electrophoresis purified thymus AChR-LP preparations contained up to 6 polypeptide bands of molecular weights of 40,000, 43,000, 51,000, 56,000, 58,000, and 66,000, respectively. The peptides of 40,000, 51,000, 56,000, and 66,000 dalton cross-reacted with the four subunits of Torpedo californica and fetal calf muscle AChR.
Kawanami
S
S
Division of Biology and Chemical Engineering, California Institute of Technology, Pasadena 91125.
Conti-Tronconi
B
B
Racs
J
J
Raftery
M A
MA
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D003039:Cobra Neurotoxin Proteins; D005333:Fetus; D008970:Molecular Weight; D011978:Receptors, Nicotinic / Q000302:isolation & purification*; D013950:Thymus Gland / Q000378:metabolism*
D000596:Amino Acids; D003039:Cobra Neurotoxin Proteins; D011978:Receptors, Nicotinic