1. The purpose and ubiquity of turnover.
- Author
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Reddien, Peter W.
- Subjects
- *
BIOLOGICAL systems , *HAZARD mitigation , *BIOLOGY , *ANTLERS , *ORGANELLES - Abstract
Turnover—constant component production and destruction—is ubiquitous in biology. Turnover occurs across organisms and scales, including for RNAs, proteins, membranes, macromolecular structures, organelles, cells, hair, feathers, nails, antlers, and teeth. For many systems, turnover might seem wasteful when degraded components are often fully functional. Some components turn over with shockingly high rates and others do not turn over at all, further making this process enigmatic. However, turnover can address fundamental problems by yielding powerful properties, including regeneration, rapid repair onset, clearance of unpredictable damage and errors, maintenance of low constitutive levels of disrepair, prevention of stable hazards, and transitions. I argue that trade-offs between turnover benefits and metabolic costs, combined with constraints on turnover, determine its presence and rates across distinct contexts. I suggest that the limits of turnover help explain aging and that turnover properties and the basis for its levels underlie this fundamental component of life. Biological systems are constantly building and destroying components. Whereas this turnover might at first seem needlessly wasteful, because degraded components are often fully functional, this Perspective describes a framework for conceptualizing how turnover at multiple scales can address fundamental challenges to maintain systems and for the basis for turnover levels. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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