M. Nakazawa et al., Biochemical analysis of the interaction between elongation factor 1 alpha and alpha/beta-tubulins from a ciliate, Tetrahymena pyriformis, FEBS LETTER, 453(1-2), 1999, pp. 29-34
The interaction between elongation factor 1 alpha(EF-1 alpha) and alpha/bet
a-tubulins has been analyzed in vivo and in vitro. An association of both a
lpha- and beta-tubulins with EF-1 alpha in the lysate of Tetrahymena pyrifo
rmis was detected by ca-immunoprecipitation analysis, In contrast, in vitro
biomolecular interaction analysis with glutathione S-transferase (GST) fus
ion proteins revealed that GST-beta-tubulin, but not GST-alpha-tubulin, can
bind to GST-EF-1 alpha. Two beta-tubulin binding sites hale been identifie
d to reside in the domains I and III of EF-1 alpha. In addition, beta-tubul
in itself seems to have two distinct interaction sites for each of the doma
ins. Since domain II of EF-1 alpha did not interact with beta-tubulin, we h
ave re-evaluated the phylogenetic status of ciliates using EF-1 alpha seque
nces devoid of domain II. The phylogenetic tree thus obtained was significa
ntly different from that inferred from the whole sequence of EF-1 alpha, su
ggesting the presence of functional constraints on the molecular evolution
of EF-1 alpha. (C) 1999 Federation of European Biochemical Societies.