UAB scientists report surprising findings regarding the enzymes that make RNA, called RNA polymerases, in a study published August 29, 2013 in Cell Reports. The findings suggest a new strategy to identify potential targets for controlling rampant cell growth, a hallmark of many cancers.
The study looked at two RNA polymerases known as polymerase I and II (Pol I and Pol II) in brewer’s yeast cells, which is an established model for higher organisms. RNA polymerases are enzymes that make RNA based on the genetic code found in DNA. Pol I and Pol II have separate but similar cellular roles. In essence, Pol I makes the RNA that forms the bulk of ribosomes - the factories that make protein - and Pol II makes RNA that the ribosomes use as templates, or recipes, for making proteins.
“Science has long assumed that any changes or mutations in similar regions of one RNA polymerase will have the same effect on related RNA polymerases,” said David Schneider, Ph.D., assistant professor in the Department of Biochemistry and Molecular Genetics and primary investigator of the study. “We found, to our surprise, that mutations in Pol I that are identical to known mutations in Pol II did not have the same effects on polymerase activity. This finding identifies unique features of Pol I that could potentially be exploited to develop drugs that target one polymerase while not interfering in function of the other.” Read more about the study.