Microbiol. Rev., 09 1995, 506-531, Vol 59, No. 3
WH Mager and AJ De Kruijff
Living cells, both prokaryotic and eukaryotic, employ specific sensory and
signalling systems to obtain and transmit information from their
environment in order to adjust cellular metabolism, growth, and development
to environmental alterations. Among external factors that trigger such
molecular communications are nutrients, ions, drugs and other compounds,
and physical parameters such as temperature and pressure. One could
consider stress imposed on cells as any disturbance of the normal growth
condition and even as any deviation from optimal growth circumstances. It
may be worthwhile to distinguish specific and general stress circumstances.
Reasoning from this angle, the extensively studied response to heat stress
on the one hand is a specific response of cells challenged with
supra-optimal temperatures. This response makes use of the sophisticated
chaperoning mechanisms playing a role during normal protein folding and
turnover. The response is aimed primarily at protection and repair of
cellular components and partly at acquisition of heat tolerance. In
addition, heat stress conditions induce a general response, in common with
other metabolically adverse circumstances leading to physiological
perturbations, such as oxidative stress or osmostress. Furthermore, it is
obvious that limitation of essential nutrients, such as glucose or amino
acids for yeasts, leads to such a metabolic response. The purpose of the
general response may be to promote rapid recovery from the stressful
condition and resumption of normal growth. This review focuses on the
changes in gene expression that occur when cells are challenged by stress,
with major emphasis on the transcription factors involved, their cognate
promoter elements, and the modulation of their activity upon stress signal
transduction. With respect to heat shock- induced changes, a wealth of
information on both prokaryotic and eukaryotic organisms, including yeasts,
is available. As far as the concept of the general (metabolic) stress
response is concerned, major attention will be paid to Saccharomyces
cerevisiae.
Copyright © 1995, American Society for Microbiology
Stress-induced transcriptional activation
Department of Biochemistry and Molecular Biology, IMBW, BioCentrum Amsterdam, Vrije Universiteit, The Netherlands.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»