/Though we have only observed UGA codons translated as tryptophan in Blepharisma stoltei, in vitro translation experiments suggest Blepharisma japonicum's ortholog of the highly transcribed B. stoltei eRF1, also with Ala67, can recognize all three stop codons, but UGA the most weakly. Correspondingly, with some capacity of Blepharisma eRF1 to recognize UGA as stop codons, a signal of potential competition between B. stoltei eRF1 and tRNA^Trp can be observed in the form of UGA codon depletion in a region beginning 25-30 codons upstream of UAR stop codons (Fig. 2b). A similar depletion was observed in the karyorelict ciliates and the heterotrich ciliate Condylostoma which do use UGA as a stop close to transcript ends.