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ABSTRACT Considerable progress has been made in understanding the physiological basis for variation in the life‐history patterns of animals, particularly with regard to the roles of oxidative stress and hormonal regulation. However, an underappreciated and understudied area that could play a role in mediating inter‐ and intraspecific variation of life history is endoplasmic reticulum (ER) stress, and the resulting unfolded protein response (UPRER). ER stress response and the UPRERmaintain proteostasis in cells by reducing the intracellular load of secretory proteins and enhancing protein folding capacity or initiating apoptosis in cells that cannot recover. Proper modulation of the ER stress response and execution of the UPRERallow animals to respond to intracellular and extracellular stressors and adapt to constantly changing environments. ER stress responses are heritable and there is considerable individual variation in UPRERphenotype in animals, suggesting that ER stress and UPRERphenotype can be subjected to natural selection. The variation in UPRERphenotype presumably reflects the way animals respond to ER stress and environmental challenges. Most of what we know about ER stress and the UPRERin animals has either come from biomedical studies using cell culture or from experiments involving conventional laboratory or agriculturally important models that exhibit limited genetic diversity. Furthermore, these studies involve the assessment of experimentally induced qualitative changes in gene expression as opposed to the quantitative variations that occur in naturally existing populations. Almost all of these studies were conducted in controlled settings that are often quite different from the conditions animals experience in nature. Herein, we review studies that investigated ER stress and the UPRERin relation to key life‐history traits including growth and development, reproduction, bioenergetics and physical performance, and ageing and senescence. We then ask if these studies can inform us about the role of ER stress and the UPRERin mediating the aforementioned life‐history traits in free‐living animals. We propose that there is a need to conduct experiments pertaining to ER stress and the UPRERin ecologically relevant settings, to characterize variation in ER stress and the UPRERin free‐living animals, and to relate the observed variation to key life‐history traits. We urge others to integrate multiple physiological systems and investigate how interactions between ER stress and oxidative stress shape life‐history trade‐offs in free‐living animals.
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The plant endoplasmic reticulum UPRome: A repository and pathway browser for genes involved in signaling networks linked to the endoplasmic reticulum
Abstract The endoplasmic reticulum (ER) houses sensors that respond to environmental stress and underly plants' adaptative responses. These sensors transduce signals that lead to changes in nuclear gene expression. The ER to nuclear signaling pathways are primarily attributed to the unfolded protein response (UPR) and are also integrated with a wide range of development, hormone, immune, and stress signaling pathways. Understanding the role of the UPR in signaling network mechanisms that associate with particular phenotypes is crucially important. While UPR‐associated genes are the subject of ongoing investigations in a few model plant systems, most remain poorly annotated, hindering the identification of candidates across plant species. This open‐source curated database provides a centralized resource of peer reviewed knowledge of ER to nuclear signaling pathways for the plant community. We provide a UPRome interactive viewer for users to navigate through the pathways and to access annotated information. The plant ER UPRome website is located athttp://uprome.tamu.edu. We welcome contributions from the researchers studying the ER UPR to incorporate additional genes into the database through the “contact us” page.
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- Award ID(s):
- 1759034
- PAR ID:
- 10369150
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Plant Direct
- Volume:
- 6
- Issue:
- 7
- ISSN:
- 2475-4455
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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