University of Minnesota
School of Physics & Astronomy

Physics and Astronomy Calendar

Thursday, May 3rd 2018
10:10 am:
Biophysics Seminar in 120 PAN
Speaker: Ibrahim Cisse, Department of Physics, Massachusetts Institute of Technology
Subject: Super-resolution imaging of transcription in living mammalian cells

Protein clustering is a hallmark of genome regulation in mammalian cells. However, these clusters often emerge from weak or transient interactions between component biomolecules at length scales and with temporal dynamics not readily attained in live cell imaging. My lab focuses on pushing single molecule and super-resolution techniques to enable the detection and characterization of weak or transient biomolecular assemblies with very high spatial and temporal resolutions directly in living mammalian cells. We discovered that very transient clusters of RNA Polymerase II (Pol II) correlate with mRNA synthesis at gene loci. For endogenous β-actin genes in live 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.

The weekly calendar is also available via subscription to the physics-announce mailing list, and by RSS feed.