Molecular cloning of the translation elongation factor 1A (eEF1A) gene from the soft coral, Scleronephthya gracillimum (Kukenthal) and implication on Cnidarian Phylogeny

Abstract

The complete cDNA of eukaryotic translation elongation factor 1A (eEF1A) from the soft coral Scleronephthya gracillimum (Kukenthal) (Alcyonacea, Octocorallia, Anthozoa, Cnidaria) was cloned by RT-PCR and the nucleotide sequences were determined. The information on primary structure of the eEF1A gene and protein may be useful for the gene expression study as well as for the phylogenetic study. The full-length cDNA of S. gracillimum eEF1A comprised 1612 bp, not including the poly (A)(+) stretch, and contained a complete open reading frame encoding 461 amino acids. The deduced amino acid sequence showed 85% identity to placozoan, 86% to human and 77% to hydra. Considering that functional domains are highly conserved throughout the evolutionary history, the present study suggests that the amino acid sequence of eEF1A alone may not resolve the phylogenetic relationship of lower metazoans. A possible solution to overcome the long branch problems that appear in cnidiarian phylogeny is discussed.