Oscillatory Expression of Hes1, p53, and NF-kB Driven by Transcriptional Time Delay

Feedback inhibition of gene expression is a wide-spread phenomenon, which means the gene is inhibited by its protein product. Feedback inhibition in eukaryotic cells involves time delays of gene expression resulting from transcription, transcript splicing and processing, and protein synthesis. In principle, such phenomenon could result in the oscillation of gene expression. However, experimental evidence of the connection is lacking. Recent data from cell lines revealed that the expression of three transcription factors (Hes1, p53 and NF-kB) are oscillatory. And each of them is a component of a short feedback inhibition loop. In this paper, the author showed a connection between the oscillation of gene expression and feedback inhibition by determination of protein and mRNA half-life. This provides direct evidence that transcriptional delays can drive oscillatory gene expression and helps analyzing genetic regulatory networks.

From: Current Biology 13: 1409-1413
 
 
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