Polymerases Pause to Help Mediate the Flow of Genetic Information
In transcription, the first step of gene expression, the information stored in DNA is copied into RNA by a molecular machine known as RNA polymerase. Rather than hurriedly transcribing a gene from start to finish, these polymerases often pause as they travel down the double helix, sometimes for as long as an hour at a time. Researchers in the Zeitlinger Lab studied the effect this pausing had on the overall process of transcription. They showed that when one polymerase pauses, it keeps other polymerases from initiating transcription. They believe that these pauses could provide a much-needed respite in between bursts of transcription to make gene expression more controlled and deliberate.
“Having traffic rules makes sense. Leaving polymerase traffic to randomness would be inefficient and dangerous.” For example, cancer can arise when gene expression is allowed to unfold unchecked. Associate Investigator and lead author Julia Zeitlinger, PhD, believes that by understanding the basic mechanisms that control gene expression, researchers can gain a greater appreciation of the underlying causes of cancer and related diseases.
This study was published online May 15, 2017, in Nature Genetics.