Ready, Set, Gonew research is helping to elucidate yet another mechanism which is the equivalent of a fine-control knob on the timing of the transcription process.
Gene transcription is conducted by a massive molecular machine known as RNA polymerase which, roughly translated into English, means to glue together many nucleotides to make an RNA molecule. The transcription process entails unwinding the DNA double helix, sliding along one of the strands, grabbing the correct matching nucleotide at each rung, and gluing that nucleotide to the end of the new and growing transcript.
But before this process begins the RNA polymerase machine may pause and wait for a start signal. Apparently in these cases the task at hand is not to be accomplished as soon as possible, but rather it is coordinated and synchronized with other activities. The timing of the arrival of the RNA polymerase is not sufficiently precise so it arrives a little early, and then is paused until just the right moment.
Not too surprisingly this pausing of RNA polymerase is particularly important in the embryonic development stages where the growing embryo is undergoing a massive and complex cellular choreography of events.
The new research helps to elucidate for which genes RNA polymerase is paused, and how this pausing regulation of RNA polymerase varies over time and between tissues.
It is yet another mechanism in the fantastically complex gene regulation.