Evolutionary cell biology: Two origins, one objective

Abstract

All aspects of biological diversification ultimately trace to evolutionary modifications at the cellular level. This central role of cells frames the basic questions as to how cells work and how cells come to be the way they are. Although these two lines of inquiry lie respectively within the traditional provenance of cell biology and evolutionary biology, a comprehensive synthesis of evolutionary and cell-biological thinking is lacking. We define evolutionary cell biology as the fusion of these two eponymous fields with the theoretical and quantitative branches of biochemistry, biophysics, and population genetics. The key goals are to develop a mechanistic understanding of general evolutionary processes, while specifically infusing cell biology with an evolutionary perspective. The full development of this interdisciplinary field has the potential to solve numerous problems in diverse areas of biology, including the degree to which selection, effectively neutral processes, historical contingencies, and/or constraints at the chemical and biophysical levels dictate patterns of variation for intracellular features. These problems can now be examined at both the within-and among-species levels, with single-cell methodologies even allowing quantification of variation within genotypes. Some results from this emerging field have already had a substantial impact on cell biology, and future findings will significantly influence applications in agriculture, medicine, environmental science, and synthetic biology.evolutionary cell biology | cell biology | adaptive evolution | random genetic drift | cellular evolutionThe origin of cells constituted one of life's most important early evolutionary transitions, simultaneously enabling replicating entities to corral the fruits of their catalytic labor and providing a unit of inheritance necessary for further evolutionary refinement and diversification. The centrality of cellular features to all aspects of biology motivates the focus of cell biology on the biophysical/biochemical aspects of a broad swath of traits that include gene expression, metabolism, intracellular transport and communication, cellcell interactions, locomotion, and growth. No one questions the rich contributions that have resulted from this focus on how cells work. However, with an emphasis on maximizing experimental consistency in a few well-characterized model systems, cell biologists have generally eschewed the variation that motivates most questions in evolutionary biology.Because all evolutionary change ultimately requires modifications at the cellular level, questioning and understanding how cellular features arise and diversify should be a central research venue in evolutionary biology. However, if there is one glaring gap in this field, it is the absence of widespread cell-biological thinking. Despite the surge of interest at the molecular, genomic, and developmental levels, much of today's study of evolution is only moderately concerned with cellular features, perhaps due to lack of appreciation for...

Endosymbiosis and its implications for evolutionary theory

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Making Sense of Transcription Networks

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Tetrahymenaas a Unicellular Model Eukaryote: Genetic and Genomic Tools

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