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Updated: May 23, 2026
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Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy
Published on: June 24, 2019
TFIIIC localizes budding yeast ETC sites to the nuclear periphery
Shin-ichiro Hiraga1, Sotirios Botsios, David Donze
1Institute of Medical Sciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom.
Molecular Biology of the Cell
|April 13, 2012
Summary
Extra TFIIIC (ETC) sites in Saccharomyces cerevisiae localize to the nuclear periphery. The transcription factor TFIIIC and Mps3 protein are crucial for this positioning, influencing chromatin architecture.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Chromatin organization is essential for proper chromosome function.
- Specific intranuclear positioning of genomic loci influences gene regulation.
- Extra TFIIIC (ETC) sites bind TFIIIC but do not recruit RNA polymerase III.
Purpose of the Study:
- To investigate the intranuclear positioning of Saccharomyces cerevisiae ETC sites.
- To determine the role of TFIIIC and other factors in ETC site localization.
- To understand the functional implications of ETC site positioning.
Main Methods:
- Analysis of ETC site localization using microscopy in Saccharomyces cerevisiae.
- Genetic manipulation of TFIIIC-binding sites and subunits (e.g., Tfc3).
- Investigating the role of Mps3, an inner nuclear membrane protein.
Main Results:
- Six of eight known S. cerevisiae ETC sites are predominantly localized at the nuclear periphery.
- TFIIIC is central to ETC site peripheral localization; mutations or degradation of TFIIIC disrupt positioning.
- Mps3 is required for ETC site peripheral localization.
- ETC sites retain tethering function when relocated, but barrier/insulator functions are independent of peripheral localization.
Conclusions:
- TFIIIC and Mps3 collaborate to direct the nuclear periphery localization of a novel class of S. cerevisiae genomic loci.
- While peripheral localization is mediated by TFIIIC and Mps3, chromatin barrier and insulator functions are not dependent on this positioning.
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