Functional Genomics of Adaptation to Hypoxic Cold-Stress in High-Altitude Deer Mice: Transcriptomic Plasticity and Thermogenic Performance

Authors

Zachary A. Cheviron, University of Illinois at Urbana-ChampaignFollow
Alex D. Connaty, McMaster University
Grant B. McClelland, McMaster UniversityFollow
Jay F. Storz, University of Nebraska-LincolnFollow

Date of this Version

9-2013

Citation

Published in Evolution (Early View), doi: 10.1111/evo.12257

Comments

Copyright © 2013 Zachary A. Cheviron, Alex D. Connaty, Grant B. McClelland, and Jay F. Storz. Published by Wiley-Blackwell. Used by permission.

Abstract

In species that are distributed across steep environmental gradients, adaptive variation in physiological performance may be attributable to transcriptional plasticity in underlying regulatory networks. Here we report the results of common-garden experiments that were designed to elucidate the role of regulatory plasticity in evolutionary adaptation to hypoxic cold-stress in deer mice (Peromyscus maniculatus). We integrated genomic transcriptional profiles with measures of metabolic enzyme activities and whole-animal thermogenic performance under hypoxia in highland (4350 m) and lowland (430 m) mice from three experimental groups: (1) wild-caught mice that were sampled at their native elevations; (2) wild-caught/labreared mice that were deacclimated to low-elevation conditions in a common-garden lab environment; and (3) the F₁ progeny of deacclimated mice that were maintained under the same low-elevation common- garden conditions. In each experimental group, highland mice exhibited greater thermogenic capacities than lowland mice, and this enhanced performance was associated with upregulation of transcriptional modules that influence several hierarchical steps in the O₂ cascade, including tissue O₂ diffusion (angiogenesis) and tissue O₂ utilization (metabolic fuel use and cellular oxidative capacity). Most of these performance-related transcriptomic changes occurred over physiological and developmental timescales, suggesting that regulatory plasticity makes important contributions to fitness-related physiological performance in highland deer mice.

6 supplemental files are attached below.