Investigating how physiologies & genomes evolve

Montooth Lab







Evolutionary genetics of energetics

Energetic traits, such as ATP levels, must be maintained as organisms adapt to different ecologies and dynamically respond to variable environments within their lifetime. These energetic traits also underlie basic processes of cell division, growth and development. We are increasingly interested in the genes and physiologies that link temperature to metabolic rates and growth rates in insects (Luke Hoekstra), as well as the developmental trajectory of respiratory structures and metabolic rate (Cole Julick, Omera Matoo).

How do the pathways underlying largely homeostatic and conserved physiological systems nevertheless harbor variation within populations, diverge among populations and evolve across phylogenies?

A temperature-sensitive genetic interaction perturbs metabolism and development

We have identified an epistatic incompatibility between mitochondrial and nuclear mutations that perturbs larval metabolic rate and development. This incompatibility is strongly dependent upon the thermal environment. Cooler temperatures mitigate and warmer temperatures magnify the deleterious effects of this energetic disruption. We are using these genotypes to better understand the physiological and genetic mechanisms that translate temperature into rates of metabolism, growth and development. In addition we are investigating temperature-sensitive defects in both oogenesis and spermatogenesis in these genotypes to better understand how temperature and metabolism affect the development of fertility (in collaboration with Brian Calvi and Colin Meiklejohn).

 The energetic costs of cellular physiology and the evolution of metabolic rate

Regulation of energy allocation impacts life history tradeoffs and physiological responses that maintain fitness across heterogeneous environments experienced within a lifetime. For example, we have found that cellular responses, such as the heat shock response, are energetically costly. We are interested in how selection shapes metabolic rate. A working model is that low resting metabolic rates are selectively favored to maximize the energy available for growth, reproduction, and physiological responses to the environment.

Representative Publications:

Greenlee, Montooth and Helm 2014 Integr Comp Biol
Hoestra, Siddiq and Montooth 2013 Genetics
Hoeksta and Montooth 2013 BMC Evol Biol
Meiklejohn et al. 2013 PLoS Genetics
Montooth et al. 2003 Genetics


Other Research:

cellular adaptation | mt-nuclear coevolution