In:
eLife, eLife Sciences Publications, Ltd, Vol. 5 ( 2016-09-30)
Abstract:
Cells respond to environmental signals by activating proteins called transcription factors. These bind to the DNA that is stored in the cell nucleus and turn on specific genes to make gene products. Many of these transcription factors move in and out of the nucleus once activated. Different environmental signals affect the amount of transcription factor that appears in the nucleus in different ways, and this is important in determining which genes should be turned on and how many copies of gene products should be made. Many transcription factors co-exist with a similar version of themselves in the same cell. These closely related proteins, called homologous transcription factors, respond to the same signals and bind to the same place on the DNA to turn on the same genes. It was not clear what advantages the cells gain from having two molecules that perform the same roles. Two homologous transcription factors called Msn2 and Msn4 are found in baker's yeast. These transcription factors respond to a wide variety of environmental stresses by moving rapidly into the nucleus, where they remain for a short time to turn on hundreds of target genes that are needed for the cell to survive. AkhavanAghdam, Sinha, Tabbaa et al. investigated the roles of Msn2 and Msn4 by tracking where the proteins localized to and which genes they switched on inside the same single cell. Genes that can be turned on quickly could be activated by either Msn2 or Msn4, and both factors activated the genes to a similar extent. By contrast, both Msn2 and Msn4 were required to activate those genes that take a long time to be turned on. In these cases, Msn2 served as a 'switch' that governed the 'on' and 'off' state of the genes, while Msn4 behaved as a 'rheostat' to tune how much gene product was made. This cooperation between the two transcription factors is equivalent to a design commonly found in electrical circuits and may help the cell to survive in rapidly changing environments. Further studies are now needed to investigate the mechanisms that provide Msn2 and Msn4 with distinct roles in gene regulation. Technological advances that allow the full genetic material of a single cell to be analyzed could also determine whether other homologous transcription factors regulate their target genes in similar ways.
Type of Medium:
Online Resource
ISSN:
2050-084X
DOI:
10.7554/eLife.18458.001
DOI:
10.7554/eLife.18458.002
DOI:
10.7554/eLife.18458.003
DOI:
10.7554/eLife.18458.004
DOI:
10.7554/eLife.18458.005
DOI:
10.7554/eLife.18458.006
DOI:
10.7554/eLife.18458.007
DOI:
10.7554/eLife.18458.008
DOI:
10.7554/eLife.18458.009
DOI:
10.7554/eLife.18458.010
DOI:
10.7554/eLife.18458.011
DOI:
10.7554/eLife.18458.012
DOI:
10.7554/eLife.18458.013
DOI:
10.7554/eLife.18458.014
DOI:
10.7554/eLife.18458.015
DOI:
10.7554/eLife.18458.016
DOI:
10.7554/eLife.18458.017
DOI:
10.7554/eLife.18458.018
DOI:
10.7554/eLife.18458.019
DOI:
10.7554/eLife.18458.020
DOI:
10.7554/eLife.18458.021
DOI:
10.7554/eLife.18458.022
DOI:
10.7554/eLife.18458.023
DOI:
10.7554/eLife.18458.024
DOI:
10.7554/eLife.18458.025
DOI:
10.7554/eLife.18458.026
DOI:
10.7554/eLife.18458.027
DOI:
10.7554/eLife.18458.028
DOI:
10.7554/eLife.18458.029
DOI:
10.7554/eLife.18458.030
DOI:
10.7554/eLife.18458.031
DOI:
10.7554/eLife.18458.032
Language:
English
Publisher:
eLife Sciences Publications, Ltd
Publication Date:
2016
detail.hit.zdb_id:
2687154-3
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