title: The purification and characterization of a Thy-1-like glycoprotein from chicken brain.
abstract: We have purified from chicken forebrain a membrane glycoprotein that is enriched in purified synaptic membranes and has an apparent mol.wt. of 22 800 in 15% sodium dodecyl sulphate/polyacrylamide gels. This molecule was compared with rat and human brain Thy-1 glycoproteins purified by the same procedure in order to determine whether it could be a homologue of Thy-1. Although polyvalent heterologous antisera raised against the rat and chicken molecules showed no immunological cross-reactivity with the other glycoprotein, a great deal of physical and chemical similarity was demonstrated between the chicken glycoprotein and rat Thy-1. Their apparent molecular weights, subcellular localization and amino acid and amino sugar compositions are very similar. C.d. spectra show that both molecules contain predominantly a beta-sheet and structure with no detectable alpha-helix. Electrophoretic analysis of the CNBr-cleaved molecules under reducing and non-reducing conditions shows that both molecules contain intramolecular disulphide bridges. Taken together these results suggest that the chicken brain glycoprotein is an immunologically distinct homologue of the mammalian Thy-1 glycoproteins.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000954:Antigens, Surface / Q000276:immunology / Q000302:isolation & purification; D001923:Brain Chemistry; D002645:Chickens; D002942:Circular Dichroism; D003488:Cyanogen Bromide; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005779:Immunodiffusion; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011952:Receptors, Concanavalin A; D013045:Species Specificity; D013570:Synaptic Membranes / Q000032:analysis; D018800:Thy-1 Antigens
chemical_list: D000596:Amino Acids; D000954:Antigens, Surface; D011952:Receptors, Concanavalin A; D018800:Thy-1 Antigens; C027774:concanavalin A-binding glycoproteins; D003488:Cyanogen Bromide