Inside your cells are thousands of spell checkers that put any human typist to shame. In a process critical to all living things, RNA Polymerase II transcribes DNA into RNA rapidly and with high fidelity. Even very similar chemical letters are accurately discriminated by this wonder of a molecular machine that is described in ScienceDaily.1

The article describes its performance as “exquisite precision” and “unerring accuracy.” RNA Polymerase II (Pol II) has been studied for years, but new secrets continue to pour forth. Two teams have gleaned more details about how the proofreading works. Mutations, they found, caused severe losses in fidelity.

The researchers said their findings not only offer unprecedented details about the fidelity mechanism of Pol II, but likely about fidelity in all cellular genetic copying machines.

What? You mean there’s more? Absolutely. From transcription to translation, each stage of protein manufacture from the DNA template is checked for errors by molecular machines. When those machines break down due to mutations, bad things happen. The last word:….

Continue Reading on