Nanotech instruments allow for observing RNA ‘proofreading’

November 26, 2003 | Source: KurzweilAI

Stanford University researchers have discovered a “proofreading” step used to correct DNA transcription errors in expressing genes from DNA to RNA to proteins.

They made the discovery while observing the molecular process used by the RNA polymerase (RNAP) enzyme to copy individual bases from E. coli bacteria DNA onto strands of RNA.

Papers published in Nature and Cell “push the study of single proteins to new limits,” says Steven M. Block, a professor of biological sciences and of applied physics at Stanford University. “We’ve been able to achieve a resolution of three angstroms — the width of three hydrogen atoms — in our measurements of the progress of this enzyme along DNA. In so doing, we’ve been able to visualize a backtracking motion of just five bases that accompanies RNAP error-correction or proofreading.”

The finding could have significant ramifications for biology and human health, since misformed proteins can lead to heart disease, Alzheimer’s, and other illnesses.