Structural Differences of Microtubule Associated Proteins from Brain Probed by Tryptic Peptide Mapping

• Published in: Journal of biochemistry (Tokyo) Vol. 100; no. 1; pp. 59 - 65
• Main Authors: TANABE, Kazushi, SATO, Chikako, KOBAYASHI, Takaaki, TAKAHASHI, Taijo
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.07.1986
• Subjects: Animals; Biological and medical sciences; brain; Brain Chemistry; Cell structures and functions; Cytoskeleton, cytoplasm. Intracellular movements; Fundamental and applied biological sciences. Psychology; microtubule-associated protein; Microtubule-Associated Proteins - isolation & purification; Molecular and cellular biology; Molecular Weight; Peptide Mapping; Rats; Species Specificity; Swine; Trypsin; Rat; Molecular structure; Rodentia; Central nervous system; Brain (Vertebrata); Homology; Pig; Peptide map; Vertebrata; Mammalia; Microtubule associated protein; Artiodactyla; Ungulata; Comparative study
• ISSN: 0021-924X
• DOI: 10.1093/oxfordjournals.jbchem.a121706

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 electro-phoresis. 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. 1) Subspecies of MAP-1 (355-345 and 325 kDa) showed about 33% homology in the tryptic peptide maps. 2) 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. 3) Subspecies of tau proteins (65 and 60 kDa) were very closely related. 4) Structural similarity between MAP-2 and tau was very low. 5) MAP-1 from porcine brain and rat brain showed very high structural homology.