Structure and expression of elongation factor 1α in tomato

Abstract

A full-length cDNA clone, LeEF-1, has been isolated from tomato for the .alpha. subunit of elongation factor 1 (EF-1.alpha.), a polypeptide which plays a central role in protein synthesis. The 448 amino acid protein encoded by this cDNA appears highly homologous to other EF-1.alpha.s having a high degree of similarity (75-78%) to EF1.alpha. previously described from both lower eukaryotes and animals. Southern analysis indicated that EF-1.alpha. belongs to a small multigene family of 4-8 members in tomato. The pattern of expression of EF-1.alpha. mRNA in various tomato tissues was analyzed by Northern analysis, in vitro translation and in situ hybridization. EF-1.alpha. mRNA is an abundant species and higher levels of mRNA were found in developing tissues such as young leaves and green fruit compared to the mRNA levels observed in older tissues. The increased levels of EF-1.alpha. mRNA therefore appear to correlate with higher levels of protein synthesis in developing tissues.