Congresos y reuniones científicas
Título:
Incorporation of L-Dopa into C-terminus of a-tubulin in cultured cells and in vivo
Autor/es:
24. DENTESANO Y, BISIG C.G , CARBAJAL A, CHESTA ME, AND ARCE C.A.
Reunión:
Congreso; XXVIII Congreso anual de la Sociedad Argentina de Investigación en Neurociencias; 2013
Institución organizadora:
SAN
Resumen:
We previously described that L-Dopa can be in vitro incorporated into the C-terminus of α-
tubulin by ?tubulin tyrosine ligase? (TTL). After its incorporation, Dopa cannot be released by ?tubulin
carboxypeptidase? (TCP), the other enzyme involved in the tyrosination/detyrosination cycle.
Dopa-tubulin, was polymerized into microtubules as well as Tyr-tubulin, and both tubulin types
disassembled similarly. To monitor and to measure the amount of Dopa incorporated into tubulin we
used a method based the analysis of the tyrosination state (% tyrosinated, % detyrosinated tubulin
with respect to total tubulin) of samples before and after Dopa incorporation.
We now report that Dopa incorporation into tubulin was also demonstrated to occur in cultured
cells in the absence of ?de novo? protein synthesis. Furthermore, once incorporated into tubulin
of cultured cells, dopa could not be removed by subsequent incubation even in the presence of
added tyrosine suggesting that dopa binds irreversibly to the COOH-terminus of α-tubulin blocking
posterior incorporation of tyrosine. Similarly, after intracraneal microinjection of L-Dopa in rats and
subsequent brain tubulin purification, we found that L-Dopa was incorporated in the COOH-terminal
of tubulin.