Analysis of a ubiquitous promoter element in a primitive eukaryote: early evolution of the initiator element.

ABSTRACT: Typical metazoan core promoter elements, such as TATA boxes and Inr motifs, have yet to be identified in early-evolving eukaryotes, underscoring the extensive divergence of these organisms. Towards the identification of core promoters in protists, we have studied transcription of protein-encoding genes in one of the earliest-diverging lineages of Eukaryota, that represented by the parasitic protist Trichomonas vaginalis. A highly conserved element, comprised of a motif similar to a metazoan initiator (Inr) element, surrounds the start site of transcription in all examined T. vaginalis genes. In contrast, a metazoan-like TATA element appears to be absent in trichomonad promoters. We demonstrate that the conserved motif found in T. vaginalis protein-encoding genes is an Inr promoter element.

SUBMITTER: Liston DR 

PROVIDER: S-EPMC84030 | biostudies-literature | 1999 Mar

REPOSITORIES: biostudies-literature