4a8j
From Proteopedia
Crystal Structure of the Elongator subcomplex Elp456
Structural highlights
FunctionELP4_YEAST Acts as component of the RNA polymerase II elongator complex, which is a major histone acetyltransferase component of the RNA polymerase II (RNAPII) holoenzyme and is involved in transcriptional elongation. Association with elongating RNAPII requires a hyperphosphorylated state of the RNAPII C-terminal domain (CTD). Elongator binds to both naked and nucleosomal DNA, can acetylate both core and nucleosomal histones, and is involved in chromatin remodeling. It acetylates histones H3, preferentially at 'Lys-14', and H4, preferentially at 'Lys-8'. It functions as a gamma-toxin target (TOT); disruption of the complex confers resistance to Kluyveromyces lactis toxin zymocin (pGKL1 killer toxin). May also be involved in sensitiviy to Pichia inositovora toxin. May be involved in tRNA modification. ELP4 is required for the complex integrity and the complex HAT activity but is not required for the association of the complex with nascent RNA transcript. Is required for an early step in synthesis of 5-methoxycarbonylmethyl (mcm5) and 5-carbamoylmethyl (ncm5) groups present on uridines at the wobble position in tRNA.[1] [2] [3] [4] [5] [6] [7] Publication Abstract from PubMedElongator 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. The Elongator subcomplex Elp456 is a hexameric RecA-like ATPase.,Glatt S, Letoquart J, Faux C, Taylor NM, Seraphin B, Muller CW Nat Struct Mol Biol. 2012 Feb 19;19(3):314-20. doi: 10.1038/nsmb.2234. PMID:22343726[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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