A cDNA clone coding for rice elongation factor 1β′(EF-1β′) was isolated from a rice anther cDNA library. The clone, named RB′, was 980 bp long and contained a single open reading frame coding for 223 amino acids; the first 31 amino acids, except for the first methionine, which is absent in the mature protein, are identical to those of the purified protein determined with a protein sequencer. The amino acid sequence of rice EF-1β′ shows homology to the C-terminal half of Artemia salina EF-1β (59%) and human EF-1β (63%), but might not have a phosphorylation site for casein kinase II which has been conserved in Artemia salina EF-1β and EF-σ, human EF-1β and silkworm EF-1β′.
