Post-translational incorporation of 3,4-dihydroxyphenylalanine into the C terminus of α-tubulin in living cells

DENTESANO, Y.M.; DITAMO, Y.; HANSEN, C. ; ARCE, C.A.; BISIG, CARLOS GASTON

FEBS JOURNAL

WILEY-BLACKWELL PUBLISHING, INC

Año: 2018 vol. 285 p. 1064 - 1064

1742-464X

he C-terminal tyrosine (Tyr) of the a-tubulin chain is subjected to posttranslationalremoval and readdition in a process termed the ?detyrosination/tyrosination cycle?. We showed in previous studies using soluble ratbrain extracts that L-3,4-dihydroxyphenylalanine (L-Dopa) is incorporatedinto the same site as Tyr. We now demonstrate that L-Dopa incorporationinto tubulin also occurs in living cells. We detected such incorporation bydetermining the ?tyrosination state? of tubulin before and after incubationof cells in the presence of L-Dopa. The presence of a tubulin isospecies followingL-Dopa incubation that was not recognized by antibodies specific toTyr- and deTyr-tubulin was presumed to reflect formation of Dopa-tubulin.L-Dopa was identified by HPLC as the C-terminal compound bound toa-tubulin. L-Dopa incorporation into tubulin was observed in Neuro 2Acells and several other cell lines, and was not due to de novo proteinbiosynthesis. Dopa-tubulin had microtubule-forming capability s