tef1, a Phytophthora infestans gene encoding translation elongation factor 1-alpha

From a set of Phytophthora infestans cDNA clones randomly selected from a potato-P. infestans interaction cDNA library, three out of 22 appeared to correspond to a gene encoding translation elongation factor 1α. The gene, called tef1, is a single copy gene in P. infestans. During the life cycle of P. infestans, tef1 is expressed in all developmental stages. Alignment and phylogeny analysis based on EF-1α proteins from several taxonomic groups, including fungi, slime molds, algae, higher plants and archeabacteria, support the view that oomycetes evolved completely independently from the true fungi. In the phylogenetic tree, P. infestans EF-1α forms one branch with EF-1α from the unicellular alga Cyanophora paradoxa, an organism belonging to a taxonomic group that occupies a key position in the evolution of plastids.