Abstract of the PDB Structure's related Publication:
Elongator was initially described as an RNA polymerase II-associated factor but has since been associated with a broad range of cellular activities. It has also attracted clinical attention because of its role in certain neurodegenerative diseases. Here we describe the crystal structure of the Saccharomyces cerevisiae subcomplex of Elongator proteins 4, 5 and 6 (Elp456). The subunits each show almost identical RecA folds that form a heterohexameric ring-like structure resembling hexameric RecA-like ATPases. This structural finding is supported by different complementary in vitro and in vivo approaches, including the specific binding of the hexameric Elp456 subcomplex to tRNAs in a manner regulated by ATP. Our results support a role of Elongator in tRNA modification, explain the importance of each of the Elp4, Elp5 and Elp6 subunits for complex integrity and suggest a model for the overall architecture of the holo-Elongator complex.
One of the six protein cofactors required for the synthesis of 5-carboxymethyl group (cm5) on the wobble uridine-34 of a few tRNA. Acetate or acetyl-CoA is the donor of acetyl group, but the detailed mechanism of the reaction is still unknown. The cm5U derivative is the intermediate for further biochemical transformation of U34 derivative to either 5-methoxycarbonylmethyl uridine (mcm5U) catalysed by Trm9/Trm112 or 5-carbamoylmethyluridine (ncm5U) catalysed by a still unknown enzyme. Mutation in Elp (especially Elp3) influences telomeric gene silencing and DNA damage response. The multi-subunit complex El1-6 also interacts with elongating RNA polymerase II (RNAPII) is thought to facilitate transcription through histone acetylation.