Related Experiment Video
Updated: May 25, 2026

Chromatin Immunoprecipitation (ChIP) to Assay Dynamic Histone Modification in Activated Gene Expression in Human Cells
Published on: July 29, 2010
Activated STAT1 transcription factors conduct distinct saltatory movements in the cell nucleus
Jasmin Speil1, Eugen Baumgart, Jan-Peter Siebrasse
1Institute of Physical and Theoretical Chemistry, Rheinische Friedrich Wilhelms University Bonn, Bonn, Germany.
Abstract:
The activation of STAT transcription factors is a critical determinant of their subcellular distribution and their ability to regulate gene expression. Yet, it is not known how activation affects the behavior of individual STAT molecules in the cytoplasm and nucleus. To investigate this issue, we injected fluorescently labeled STAT1 in living HeLa cells and traced them by single-molecule microscopy. We determined that STAT1 moved stochastically in the cytoplasm and nucleus with very short residence times (<0.03 s) before activation. Upon activation, STAT1 mobility in the cytoplasm decreased ∼2.5-fold, indicating reduced movement of STAT1/importinα/β complexes to the nucleus. In the nucleus, activated STAT1 displayed a distinct saltatory mobility, with residence times of up to 5 s and intermittent diffusive motion. In this manner, activated STAT1 factors can occupy their putative chromatin target sites within ∼2 s. These results provide a better understanding of the timescales on which cellular signaling and regulated gene transcription operate at the single-molecule level.
Related Concept Videos
The JAK-STAT Signaling Pathway
Eukaryotic Transcription Activators
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These domains are...
General Transcription Factors
Co-activators and Co-repressors
RNA Polymerase II Accessory Proteins
Transcription Factors

