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NatA acetyltransferase(Nα acetyltransferase), is an enzyme that serves to catalyze the addition of acetyl groups to various proteins emerging from the ribosome. Upon translation, the NatA binds to the ribosome and then "stretches" to the front end of the forming, or nascent, polypeptide, where it adds this acetyl group. This acetyl group is added to the front end, or N-terminus of the new protein. Forty percent of all proteins in the yeast proteome are thought to be N-terminally acetylated, with a corresponding figure of 90% in mammalian proteins.〔Caesar, Robert, Jonas Warringer, and Anders Blomberg. "Physiological Importance and Identification of Novel Targets for the N-Terminal Acetyltransferase NatB – Caesar et al. 5 (2): 368 --." Eukaryotic Cell. 16 December 2005. Web. 31 January 2010. To be specific, NatA is the main N-terminal acetyltransferase in the yeast cytosol, responsible for the acetylation of proteins at locations in which L-serine, L-alanine, L-threonine, or glycine are present.〔Gautschi, Matthias, Sören Just, Andrej Mun, Suzanne Ross, Peter Rücknagel, Yves Dubaquié, Ann Ehrenhofer-Murray, and Sabine Rospert. "The Yeast N-Acetyltransferase NatA Is Quantitatively Anchored to the Ribosome and Interacts with Nascent Polypeptides." (2003). Molecular and Cellular Biology. Web. 22 January 2010. NatA Acetyltransferase is not a single protein but a complex of three subunits. ==Sup35p acetylation== In ''Saccharomyces cerevisiae'' NatA acetyltransferase interacts with the Sup35p protein. It is involved in the reaction of the (), converting the () to its own conformation. Thus, () strains deficient in NatA Acetyltransferase have been found to have an altered interaction between Sup35p() and nascent Sup35p. This interaction at the post-translational level still produces a prion with classical beta sheets, but this version of the interaction does not take away the function of this third release factor. Thus, stop codons are translated reliably in () strains lacking NatA Acetyltransferase.〔"The NatA Acetyltransferase Couples Sup35 Prion Complexes to the () Phenotype – Pezza ''et al''. 20 (3): 1068– ." Molecular Biology of the Cell. (2008) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「NatA acetyltransferase」の詳細全文を読む スポンサード リンク
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