RNA Polymerase II cluster dynamics predict mRNA output in living cells
- Massachusetts Institute of Technology, United States
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.
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© 2016, Cho et al.
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RNA Polymerase II cluster dynamics predict mRNA output in living cells
eLife 5:e13617.
https://doi.org/10.7554/eLife.13617
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