Assoc. Prof. Dr. Alexey A. Sukhotin
Projects & Publications
Contribution of Cell Size and Number of Mitochondria to Metabolic Allometry in Ectotherms
The metabolic rate is a fundamental biological characteristic that determines the physiological and vital parameters of organisms and hence their adaptability and ecological role. Metabolic rate is highly dependent on body size of living organisms, and this phenomenon is called metabolic allometry (MA). Mass-specific metabolic rate decreases with increasing body size, so that larger organisms have a lower energy turnover rate per unit mass than smaller organisms. This pattern holds true both when comparing animals of different taxa, and within the same species, and even within a single individual in ontogeny. Search for the causes and mechanisms of MA has a long history and is still one of the important open questions in biology.
Obviously, the whole-animal metabolic rate is associated with the metabolism of tissues and organs, which, in turn, is determined by cellular energetics and the functioning of subcellular organelles – mitochondria. We assume that the allometry of cellular metabolism and of mitochondrial activity can help to explain the phenomenon of MA at the organism level. The goal of our project is to reveal the relationship between ultrastructural changes in tissues – quantitative and morphological characteristics of mitochondria – and body mass. We explore the contribution of the cell size, as well as abundance, volume, morphology and functional properties of mitochondria to the MA in marine invertebrates.