# Single-molecule visualization of transcription regulation mechanisms

> **NIH NIH R01** · BRANDEIS UNIVERSITY · 2020 · $444,250

## Abstract

Project Summary
 A central concern of the present post-genomic era of biology is understanding the chemical and physical
mechanisms by which gene expression is regulated. Appropriate activation and repression of particular genes
is necessary for maintaining normal cell function and is required for executing the programs of cell
differentiation that are essential to the development of multicellular organisms. Collectively, gene regulatory
systems are the “molecular brain” of the cell that allow it to respond appropriately to environmental stimuli.
Many cancers and other diseases result from deranged gene regulation.
 In this research project, we have developed and applied a powerful approach to quantitatively defining the
dynamic molecular mechanisms of transcription and transcription regulation in vitro. Instead of studying
populations of molecules, we directly visualize the RNA polymerase and associated regulatory proteins on
isolated single DNA molecules, following the progression of the molecular machinery through its different
states in real time while simultaneously observing the transcription reaction itself. Such direct visualization is
made possible by a multi-wavelength single-molecule fluorescence microscopy approach we call CoSMoS
(colocalization single-molecule spectroscopy). In this application, we propose applying the CoSMoS approach
to elucidating the dynamic mechanisms of selected processes involved in regulation of transcription initiation
and elongation using both bacterial and eukaryotic RNA polymerases and regulatory proteins in transcription
reactions in vitro. Our goals are: 1) Reveal how two different secondary channel binding proteins exert their
regulatory functions through a single shared target site on RNA polymerase. 2) Elucidate the mechanisms by
which bacterial elongation complexes are loaded with and regulated by general elongation factors NusA and
NusG. 3) Reveal recruitment and competition within sets of general elongation factors in yeast RNA
polymerase II elongation complexes.

## Key facts

- **NIH application ID:** 9974077
- **Project number:** 2R01GM081648-13
- **Recipient organization:** BRANDEIS UNIVERSITY
- **Principal Investigator:** JEFF GELLES
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $444,250
- **Award type:** 2
- **Project period:** 2007-07-15 → 2024-02-29

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9974077

## Citation

> US National Institutes of Health, RePORTER application 9974077, Single-molecule visualization of transcription regulation mechanisms (2R01GM081648-13). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9974077. Licensed CC0.

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