RNA Polymerase II cluster dynamics predict mRNA output in living cells
Abstract
Protein clustering is a hallmark of genome regulation in mammalian cells. However, the dynamic molecular processes involved make it difficult to correlate clustering with functional consequences in vivo. We developed a live-cell super-resolution approach to uncover the correlation between mRNA synthesis and the dynamics of RNA Polymerase II (Pol II) clusters at a gene locus. For endogenous β-actin genes in mouse embryonic fibroblasts, we observe that short-lived (~8 s) Pol II clusters correlate with basal mRNA output. During serum stimulation, a stereotyped increase in Pol II cluster lifetime correlates with a proportionate increase in the number of mRNAs synthesized. Our findings suggest that transient clustering of Pol II may constitute a pre-transcriptional regulatory event that predictably modulates nascent mRNA output.
Article and author information
Author details
Reviewing Editor
- Xiaowei Zhuang, Howard Hughes Medical Institute, Harvard University, United States
Version history
- Received: December 8, 2015
- Accepted: May 2, 2016
- Accepted Manuscript published: May 3, 2016 (version 1)
- Version of Record published: June 30, 2016 (version 2)
Copyright
© 2016, Cho et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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