title: Structural differences of microtubule associated proteins from brain probed by tryptic peptide mapping.
abstract: Microtubules were purified from porcine brain by two cycles of temperature-dependent assembly and disassembly, then microtubule associated proteins, MAP-1, MAP-2, and tau, were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Two-dimensional tryptic peptide maps of radioiodinated polypeptides were compared with each other by means of mixed sample experiments, and the following results were obtained. Subspecies of MAP-1 (355-345 and 325 kDa) showed about 33% homology in the tryptic peptide maps. Structural homology of MAP-1 and MAP-2 was very low; only 3 out of 40 peptide spots of MAP-2 were identical with those of MAP-1-C. Subspecies of tau proteins (65 and 60 kDa) were very closely related. Structural similarity between MAP-2 and tau was very low. MAP-1 from porcine brain and rat brain showed very high structural homology.
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D008869:Microtubule-Associated Proteins / Q000302:isolation & purification*; D008970:Molecular Weight; D010449:Peptide Mapping; D051381:Rats; D013045:Species Specificity; D013552:Swine; D014357:Trypsin
chemical_list: D008869:Microtubule-Associated Proteins; D014357:Trypsin