Cell Biology

Remodeling Responses

Science Signaling  10 May 2011:
Vol. 4, Issue 172, pp. ec137
DOI: 10.1126/scisignal.4172ec137

The ability to measure responses of cellular signaling systems in single cells allows investigators to characterize the ways each cell optimizes responses to external cues. In studies on mitogen-activated protein kinase (MAPK) signaling in yeast cells, Pelet et al. discovered that there was a linear relation between an osmotic stimulus and the amount of activated MAPK (in this case, Hog1) translocated to the nucleus and its retention time in the nucleus. Hog1 causes transcription of stress-response genes, but unlike the expected response of the kinase, gene activation was bimodal and varied even within the same cell. Further experiments and mathematical modeling showed that this variation corresponded to chromatin remodeling.

S. Pelet, F. Rudolf, M. Nadal-Ribelles, E. de Nadal, F. Posas, M. Peter, Transient activation of the HOG MAPK pathway regulates bimodal gene expression. Science 332, 732–735 (2011). [Abstract] [Full Text]