title: Tyrosinatable and non-tyrosinatable tubulin subpopulations in rat muscle in comparison with those in brain.
abstract: Using immunobinding and enzymatic assays we determined in rat muscle extracts the proportion of tyrosinatable tubulin, that is, tubulin that participates in the tyrosination/detyrosination cycle. We found that in muscle, in contrast with nervous tissue, practically all tubulin molecules are tyrosinatable. In the case of rat brain the non-tyrosinatable tubulin pool accounts for about 50% of the tubulin. In addition, isolectrofocusing of 14C-tyrosinated tubulin from brain and muscle extracts revealed a different composition in tyrosinatable tubulin isotypes. One of the isotypes, which in muscle accounts for 86% of the 14C-tyrosinated tubulin species, was detyrosinated by the action of tubulin carboxypeptidase faster than the rest of the 14C-tyrosinated tubulin isotypes taken in whole. In the case of brain extract, that isotype accounts for only 16% of the labeled tubulin.
authors: Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina.
authors: A C
authors: AC
authors: Alonso
authors: C A
authors: CA
authors: Arce
authors: H S
authors: HS
authors: Barra
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology; D002250:Carbon Radioisotopes; D002268:Carboxypeptidases; D043422:Carboxypeptidases A; D008870:Microtubules / Q000737:chemistry; D009132:Muscles / Q000737:chemistry*; D051381:Rats; D014404:Tubulin / Q000032:analysis / Q000737:chemistry* / Q000276:immunology; D014443:Tyrosine
chemical_list: D000906:Antibodies; D002250:Carbon Radioisotopes; D014404:Tubulin; D014443:Tyrosine; D002268:Carboxypeptidases; D043422:Carboxypeptidases A