Functional characterization of the promoter region of the chicken elongation factor-2 gene

Elongation factor 2 (EF-2) plays a key role in the essential process of protein synthesis by translocating tRNAs from the ribosomal A- and P-sites to the P- and E-sites. EF-2 regulates the outcome of protein synthesis in mammalian cells. This report demonstrates that chicken EF-2 protein levels are dependent on transcription in 8-bromo-cAMP, insulin and phorbol ester-treated cells. In order to delineate functional domains that control chicken EF-2 gene transcription, the 5′-flanking region of the chicken EF-2 promoter was analyzed. Deletion constructs from − 550 and − 86 had the same basal level promoter activity as the whole EF-2 promoter. The sequence between nucleotides − 700 and − 550 was determined to be a regulatory region for the chicken EF-2 basal promoter activity. The region between − 700 and − 550 has a negative regulatory region and two regulatory proteins (I, II). 8-bromo-cAMP increased chicken EF-2 promoter activity (− 700/+ 102) in Rat 1 HIR fibroblast cells more than insulin and phorbol ester treatment. Binding of protein I and II were decreased by 8-bromo-cAMP but restored by a protein kinase A inhibitor (KT5720). GATA consensus sequence oligonucleotide and fragment − 86/− 50 prevented protein II binding of fragment − 700/− 550. This result suggested that protein II is a GATA-like protein. These observations provide a novel regulatory mechanism for the EF-2 promoter.