Step-by-step explanation:
RNA polymerase II is inhibited by certain drugs and toxins. One well-known inhibitor of RNA polymerase II is a toxin called α-amanitin, which is found in some species of poisonous mushrooms, such as the death cap mushroom (Amanita phalloides).
α-Amanitin functions by binding to RNA polymerase II and preventing it from transcribing messenger RNA (mRNA). This inhibition of mRNA synthesis disrupts the process of protein production in eukaryotic cells, which can ultimately lead to cell death and various toxic effects in the affected organism.
It's important to note that inhibition of RNA polymerase II is highly toxic and can be fatal if ingested. Poisoning from mushrooms containing α-amanitin can result in severe liver and kidney damage. If there is a suspicion of mushroom poisoning, immediate medical attention is crucial.