Tracking transcription factor mobility and interaction in Arabidopsis roots with fluorescence correlation spectroscopy
- North Carolina State University, United States
- University of California, Irvine, United States
- Howard Hughes Medical Institute, Duke University, United States
- Wageningen University, Netherlands
Abstract
To understand complex regulatory processes in multicellular organisms, it is critical to be able to quantitatively analyze protein movement and protein-protein interactions in time and space. During Arabidopsis development, the intercellular movement of SHORTROOT (SHR) and subsequent interaction with its downstream target SCARECROW (SCR) control root patterning and cell fate specification. However, quantitative information about the spatio-temporal dynamics of SHR movement and SHR-SCR interaction is currently unavailable. Here, we quantify parameters including SHR mobility, oligomeric state, and association with SCR using a combination of Fluorescent Correlation Spectroscopy (FCS) techniques. We then incorporate these parameters into a mathematical model of SHR and SCR, which shows that SHR reaches a steady state in minutes, while SCR and the SHR-SCR complex reach a steady-state between 18 and 24 hours. Our model reveals the timing of SHR and SCR dynamics and allows us to understand how protein movement and protein-protein stoichiometry contribute to development.
Article and author information
Author details
Reviewing Editor
- Dominique C Bergmann, Stanford University/HHMI, United States
Version history
- Received: January 27, 2016
- Accepted: June 10, 2016
- Accepted Manuscript published: June 11, 2016 (version 1)
- Version of Record published: July 15, 2016 (version 2)
Copyright
© 2016, Clark et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Tracking transcription factor mobility and interaction in Arabidopsis roots with fluorescence correlation spectroscopy
eLife 5:e14770.
https://doi.org/10.7554/eLife.14770
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