RNA polymerase II subunit D / DNA-directed RNA polymerase II subunit RPB11-a / DNA-directed RNA polymerases I, II, and III subunit RPABC2 / DNA-directed RNA polymerases I, II, and III subunit RPABC3 / DNA-directed RNA polymerase II subunit RPB3 / DNA-directed RNA polymerase subunit beta / DNA-directed RNA polymerase subunit / DNA-directed RNA polymerase II subunit RPB7 / RNA polymerase II, I and III subunit K / DNA-directed RNA polymerase II subunit E ...RNA polymerase II subunit D / DNA-directed RNA polymerase II subunit RPB11-a / DNA-directed RNA polymerases I, II, and III subunit RPABC2 / DNA-directed RNA polymerases I, II, and III subunit RPABC3 / DNA-directed RNA polymerase II subunit RPB3 / DNA-directed RNA polymerase subunit beta / DNA-directed RNA polymerase subunit / DNA-directed RNA polymerase II subunit RPB7 / RNA polymerase II, I and III subunit K / DNA-directed RNA polymerase II subunit E / DNA-directed RNA polymerase II subunit RPB9 / Alpha-amanitin proprotein 類似検索 - 構成要素
生物種
Sus scrofa (ブタ) / synthetic construct (人工物) / Amanita phalloides (タマゴテングタケ) / Sus Scrofa (ブタ)
ジャーナル: J Biol Chem / 年: 2018 タイトル: Cryo-EM structure of a mammalian RNA polymerase II elongation complex inhibited by α-amanitin. 著者: Xiangyang Liu / Lucas Farnung / Christoph Wigge / Patrick Cramer / 要旨: RNA polymerase II (Pol II) is the central enzyme that transcribes eukaryotic protein-coding genes to produce mRNA. The mushroom toxin α-amanitin binds Pol II and inhibits transcription at the step ...RNA polymerase II (Pol II) is the central enzyme that transcribes eukaryotic protein-coding genes to produce mRNA. The mushroom toxin α-amanitin binds Pol II and inhibits transcription at the step of RNA chain elongation. Pol II from yeast binds α-amanitin with micromolar affinity, whereas metazoan Pol II enzymes exhibit nanomolar affinities. Here, we present the high-resolution cryo-EM structure of α-amanitin bound to and inhibited by its natural target, the mammalian Pol II elongation complex. The structure revealed that the toxin is located in a pocket previously identified in yeast Pol II but forms additional contacts with metazoan-specific residues, which explains why its affinity to mammalian Pol II is ∼3000 times higher than for yeast Pol II. Our work provides the structural basis for the inhibition of mammalian Pol II by the natural toxin α-amanitin and highlights that cryo-EM is well suited to studying interactions of a small molecule with its macromolecular target.