2024/11/01 by Mihaela Pavličev, James DiFrisco, Alan C. Love +1 · 1 voice
Biochemistry, Genetics and Molecular Biology · Medicine · #Diet and metabolism studies #Genetics, Aging, and Longevity in Model Organisms
paper · pdf · doi:10.1098/rsbl.2024.0490
openalex publication_date 2024/11/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Although evolutionary transitions of individuality have been extensively theorized, little attention has been paid to the origin of levels of organization within organisms. How and why do specialized cells become organized into specialized tissues or organs? What spurs a transition in organizational level in cases where the function is already present in constituent cell types? We propose a hypothesis for this kind of evolutionary transition based on two features of cellular metabolism: metabolic constraints on functional performance and the capacity for metabolic complementation between parenchymal and supporting cells. These features suggest a scenario whereby pre-existing specialized cell types are integrated into tissues when changes to the internal or external environment favour offloading metabolic burdens from a primary specialized cell type onto supporting cells. We illustrate this process of 'supra-functionalization' using the nervous system and pancreas.