BARLEY ELONGATION-FACTOR 1-ALPHA - GENOMIC ORGANIZATION, DNA-SEQUENCE, AND PHYLOGENETIC IMPLICATIONS

A full length cDNA clone encoding the 447 amino acid long barley (Hord eum vulgare cv. Bomi) endosperm elongation factor 1 alpha (eF-1 alpha) was isolated by a differential screening procedure. RFLP mapping of e F-1 alpha showed that the barley genome contains a small eF-1 alpha ge ne family of 4 copies, with 1 copy of the gene being located on each o f chromosomes 2, 4, 6, and 7. Analysis of barley endosperm total prote ins by Western blot with antibodies directed towards wheat eF-1 alpha and the sea urchin 51 kDa proteins gave a single band of the expected molecular weight. Amino acid sequence comparison with other plant eF-1 alpha sequences showed that the isolated barley endosperm eF-1 alpha is more similar to the published wheat eF-1 alpha sequence than to eF- 1 alpha sequences previously published for the barley cultivars Igri a nd Dicktoo. The phylogenetic analysis suggests that the barley eFla ge ne family can be divided into two subfamilies and that two ancestral g enes existed before the divergence of monocotyledonous and dicotyledon ous plants.