The cellular stress response (CSR) is pervasive to all domains of life. It has shaped the interaction between organisms and their environment since the origin of the first cell. Although the CSR has been subject to a myriad of nuanced modifications in the various branches of life present today, its core features remain preserved. The scientific literature covering the CSR is enormous and the broad scope of this brief overview was challenging. However, it is critical to conceptually understand how cells respond to stress in a holistic sense and to point out how fundamental aspects of the CSR framework are integrated. It was necessary to be extremely selective and not feasible to even mention many interesting and important developments in this expansive field. The purpose of this overview is to sketch out general and emerging CSR concepts with an emphasis on the initial cellular strain resulting from stress (macromolecular damage) and the evolutionarily most highly conserved elements of the CSR. Examples emphasize fish and aquatic invertebrates to highlight what is known in organisms beyond mammals, yeast, and other common models. Nonetheless, select pioneering studies using canonical models are also considered and the concepts discussed are applicable to all cells. More detail on important aspects of the CSR in aquatic animals is provided in the accompanying articles of this special issue.
Stress represents a multi‐faceted force that is central for the evolution of life. Organisms evolve while adapting to stress and stressful contexts often represent selective bottlenecks. To understand stress effects on biological systems and corresponding coping strategies it is imperative to properly define stress and the resulting strain that triggers compensatory responses in cells and organisms. Here I am deriving such definitions for biological systems based on principles that are established in physics. The relationship between homeostasis of critical biological variables, the elastic limit, the cellular stress response (CSR), cellular homeostasis response (CHR), system dysregulation, and the breaking point (death of the system) is outlined. Dysregulation of homeostatic set‐points of biological variables perturbs the functional properties of the system, shifting them out of the evolutionarily optimized range. Such shifts are accompanied by elevated rates of macromolecular damage, which represents a nonspecific signal for induction of a universal response, the CSR. The CSR complements the CHR in re‐establishing homeostasis of the system as a whole. Moreover, the CSR is essential for coping with suboptimal conditions while the system is in a dysregulated state and for removing excessive damage that accumulates during such periods. The extreme complexity of biological systems and their emergent properties often necessitate monitoring stress effects on many biological variables simultaneously to properly deduce stress effects on the system as a whole. Therefore, increased utilization of systems biology (omics) approaches for characterizing cellular and organismal stress responses facilitates the reductionist dissection of biological stress response mechanisms.
more » « less- Award ID(s):
- 1656371
- NSF-PAR ID:
- 10129688
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Experimental Zoology Part A: Ecological and Integrative Physiology
- Volume:
- 333
- Issue:
- 6
- ISSN:
- 2471-5638
- Page Range / eLocation ID:
- p. 350-358
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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