1
|
Latchney SE, Cadney MD, Hopkins A, Garland T. Maternal upbringing and selective breeding for voluntary exercise behavior modify patterns of DNA methylation and expression of genes in the mouse brain. GENES, BRAIN, AND BEHAVIOR 2023; 22:e12858. [PMID: 37519068 PMCID: PMC10733581 DOI: 10.1111/gbb.12858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/26/2023] [Accepted: 07/12/2023] [Indexed: 08/01/2023]
Abstract
Selective breeding has been utilized to study the genetic basis of exercise behavior, but research suggests that epigenetic mechanisms, such as DNA methylation, also contribute to this behavior. In a previous study, we demonstrated that the brains of mice from a genetically selected high runner (HR) line have sex-specific changes in DNA methylation patterns in genes known to be genomically imprinted compared to those from a non-selected control (C) line. Through cross-fostering, we also found that maternal upbringing can modify the DNA methylation patterns of additional genes. Here, we identify an additional set of genes in which DNA methylation patterns and gene expression may be altered by selection for increased wheel-running activity and maternal upbringing. We performed bisulfite sequencing and gene expression assays of 14 genes in the brain and found alterations in DNA methylation and gene expression for Bdnf, Pde4d and Grin2b. Decreases in Bdnf methylation correlated with significant increases in Bdnf gene expression in the hippocampus of HR compared to C mice. Cross-fostering also influenced the DNA methylation patterns for Pde4d in the cortex and Grin2b in the hippocampus, with associated changes in gene expression. We also found that the DNA methylation patterns for Atrx and Oxtr in the cortex and Atrx and Bdnf in the hippocampus were further modified by sex. Together with our previous study, these results suggest that DNA methylation and the resulting change in gene expression may interact with early-life influences to shape adult exercise behavior.
Collapse
Affiliation(s)
- Sarah E. Latchney
- Department of BiologySt. Mary's College of MarylandSt. Mary's CityMarylandUSA
| | - Marcell D. Cadney
- Department of Evolution, Ecology, and Organismal BiologyUniversity of CaliforniaRiversideCaliforniaUSA
- Neuroscience Research Institute, University of CaliforniaSanta BarbaraCaliforniaUSA
| | | | - Theodore Garland
- Department of Evolution, Ecology, and Organismal BiologyUniversity of CaliforniaRiversideCaliforniaUSA
| |
Collapse
|
2
|
Leszczynski EC, Schwartz NE, McPeek AC, Currie KD, Ferguson DP, Garland T. Selectively breeding for high voluntary physical activity in female mice does not bestow inherent characteristics that resemble eccentric remodeling of the heart, but the mini-muscle phenotype does. SPORTS MEDICINE AND HEALTH SCIENCE 2023; 5:205-212. [PMID: 37753423 PMCID: PMC10518799 DOI: 10.1016/j.smhs.2023.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 05/18/2023] [Accepted: 07/05/2023] [Indexed: 09/28/2023] Open
Abstract
Physical activity engagement results in a variety of positive health outcomes, including a reduction in cardiovascular disease risk partially due to eccentric remodeling of the heart. The purpose of this investigation was to determine if four replicate lines of High Runner mice that have been selectively bred for voluntary exercise on wheels have a cardiac phenotype that resembles the outcome of eccentric remodeling. Adult females (average age 55 days) from the 4 High Runner and 4 non-selected control lines were anaesthetized via vaporized isoflurane, then echocardiographic images were collected and analyzed for structural and functional differences. High Runner mice in general had lower ejection fractions compared to control mice lines (2-tailed p = 0.023 6) and tended to have thicker walls of the anterior portion of the left ventricle (p = 0.065). However, a subset of the High Runner individuals, termed mini-muscle mice, had greater ejection fraction (p = 0.000 6), fractional shortening percentage (p < 0.000 1), and ventricular mass at dissection (p < 0.002 7 with body mass as a covariate) compared to non-mini muscle mice. Mice from replicate lines bred for high voluntary exercise did not all have inherent positive cardiac functional or structural characteristics, although a genetically unique subset of mini-muscle individuals did have greater functional cardiac characteristics, which in conjunction with their previously described peripheral aerobic enhancements (e.g., increased capillarity) would partially account for their increased V ˙ O2max.
Collapse
Affiliation(s)
| | - Nicole E. Schwartz
- Department of Evolution, Ecology, and Organismal Biology, University of California Riverside, Riverside, CA, USA
| | - Ashley C. McPeek
- Department of Kinesiology, Michigan State University, East Lansing, MI, USA
| | | | - David P. Ferguson
- Department of Kinesiology, Michigan State University, East Lansing, MI, USA
| | - Theodore Garland
- Department of Evolution, Ecology, and Organismal Biology, University of California Riverside, Riverside, CA, USA
| |
Collapse
|
3
|
Latchney SE, Cadney MD, Hopkins A, Garland T. DNA Methylation Analysis of Imprinted Genes in the Cortex and Hippocampus of Cross-Fostered Mice Selectively Bred for Increased Voluntary Wheel-Running. Behav Genet 2022; 52:281-297. [PMID: 35988119 PMCID: PMC9463359 DOI: 10.1007/s10519-022-10112-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 07/26/2022] [Indexed: 11/03/2022]
Abstract
AbstractWe have previously shown that high runner (HR) mice (from a line genetically selected for increased wheel-running behavior) have distinct, genetically based, neurobiological phenotypes as compared with non-selected control (C) mice. However, developmental programming effects during early life, including maternal care and parent-of-origin-dependent expression of imprinted genes, can also contribute to variation in physical activity. Here, we used cross-fostering to address two questions. First, do HR mice have altered DNA methylation profiles of imprinted genes in the brain compared to C mice? Second, does maternal upbringing further modify the DNA methylation status of these imprinted genes? To address these questions, we cross-fostered all offspring at birth to create four experimental groups: C pups to other C dams, HR pups to other HR dams, C pups to HR dams, and HR pups to C dams. Bisulfite sequencing of 16 imprinted genes in the cortex and hippocampus revealed that the HR line had altered DNA methylation patterns of the paternally imprinted genes, Rasgrf1 and Zdbf2, as compared with the C line. Both fostering between the HR and C lines and sex modified the DNA methylation profiles for the paternally expressed genes Mest, Peg3, Igf2, Snrpn, and Impact. Ig-DMR, a gene with multiple paternal and maternal imprinted clusters, was also affected by maternal upbringing and sex. Our results suggest that differential methylation patterns of imprinted genes in the brain could contribute to evolutionary increases in wheel-running behavior and are also dependent on maternal upbringing and sex.
Collapse
|
4
|
Ferguson DP, Leszczynski EC, McPeek AC, Pendergrast LA, Visker JR, Triplett AN. Physical Activity Engagement Worsens Health Outcomes and Limits Exercise Capacity in Growth-restricted Mice. Med Sci Sports Exerc 2021; 53:1561-1571. [PMID: 34261989 PMCID: PMC10797723 DOI: 10.1249/mss.0000000000002620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION A total of 161 million children a year are growth restricted, leading to a 47% increased risk of chronic disease in adulthood. Physical activity (PA) reduces the risk of mortality from chronic disease. The purpose of the present investigation was to determine the effect of a PA intervention (wheel running) on cardiac and skeletal muscle capacities in gestational (GUN) and postnatal (PUN) growth-restricted mice as compared with nonrestricted controls (CON). METHODS A low-protein cross-fostering FVB mouse model was used to induce growth restriction during gestation and the first 21 d of postnatal life. Mouse pups were recovered on a healthy diet until mature and provided wheel access for 3 wk. At completion of the PA intervention, mice underwent maximal exercise testing on a treadmill, echocardiography, and skeletal muscle histology. RESULTS After the PA intervention, CON mice had a 45% improvement in maximal exercise capacity (P = 0.0390) because of cardiac and skeletal muscle adaptations, but GUN and PUN mice did not. Alarmingly, PUN female mice exposed to wheels had 11.45% lower left ventricular volume (P = 0.0540) and 18% lower left ventricle area (P = 0.0585), with blood flow velocities indicative of cardiac fibrosis (GUN had elevated isovolumetric contraction time P = 0.0374; GUN females and PUN males had longer isovolumetric relaxation time P = 0.0703). PUN male mice had mixed skeletal muscle responses with an oxidative shift in the diaphragm (P = 0.0162) but a glycolytic shift in the extensor digitorum longus (P = 0.0647). PUN female mice had a glycolytic shift in the soleus after wheel running. CONCLUSIONS Unexpectedly, growth-restricted mice were nonresponders to a PA intervention and displayed negative cardiac outcomes.
Collapse
Affiliation(s)
- David P Ferguson
- Department of Kinesiology, Michigan State University, East Lansing, MI
| | | | - Ashley C McPeek
- Department of Kinesiology, Michigan State University, East Lansing, MI
| | | | | | - Ashley N Triplett
- Department of Kinesiology, Michigan State University, East Lansing, MI
| |
Collapse
|
5
|
Hillis DA, Yadgary L, Weinstock GM, Pardo-Manuel de Villena F, Pomp D, Fowler AS, Xu S, Chan F, Garland T. Genetic Basis of Aerobically Supported Voluntary Exercise: Results from a Selection Experiment with House Mice. Genetics 2020; 216:781-804. [PMID: 32978270 PMCID: PMC7648575 DOI: 10.1534/genetics.120.303668] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 09/18/2020] [Indexed: 12/14/2022] Open
Abstract
The biological basis of exercise behavior is increasingly relevant for maintaining healthy lifestyles. Various quantitative genetic studies and selection experiments have conclusively demonstrated substantial heritability for exercise behavior in both humans and laboratory rodents. In the "High Runner" selection experiment, four replicate lines of Mus domesticus were bred for high voluntary wheel running (HR), along with four nonselected control (C) lines. After 61 generations, the genomes of 79 mice (9-10 from each line) were fully sequenced and single nucleotide polymorphisms (SNPs) were identified. We used nested ANOVA with MIVQUE estimation and other approaches to compare allele frequencies between the HR and C lines for both SNPs and haplotypes. Approximately 61 genomic regions, across all somatic chromosomes, showed evidence of differentiation; 12 of these regions were differentiated by all methods of analysis. Gene function was inferred largely using Panther gene ontology terms and KO phenotypes associated with genes of interest. Some of the differentiated genes are known to be associated with behavior/motivational systems and/or athletic ability, including Sorl1, Dach1, and Cdh10 Sorl1 is a sorting protein associated with cholinergic neuron morphology, vascular wound healing, and metabolism. Dach1 is associated with limb bud development and neural differentiation. Cdh10 is a calcium ion binding protein associated with phrenic neurons. Overall, these results indicate that selective breeding for high voluntary exercise has resulted in changes in allele frequencies for multiple genes associated with both motivation and ability for endurance exercise, providing candidate genes that may explain phenotypic changes observed in previous studies.
Collapse
Affiliation(s)
- David A Hillis
- Genetics, Genomics, and Bioinformatics Graduate Program, University of California, Riverside, California 92521
| | - Liran Yadgary
- Department of Genetics, University of North Carolina at Chapel Hill, North Carolina 27599
| | - George M Weinstock
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut 06032
| | | | - Daniel Pomp
- Department of Genetics, University of North Carolina at Chapel Hill, North Carolina 27599
| | - Alexandra S Fowler
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, California 92521
| | - Shizhong Xu
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521
| | - Frank Chan
- Friedrich Miescher Laboratory of the Max Planck Society, 72076 Tübingen, Germany
| | - Theodore Garland
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, California 92521
| |
Collapse
|
6
|
McGivney BA, Hernandez B, Katz LM, MacHugh DE, McGovern SP, Parnell AC, Wiencko HL, Hill EW. A genomic prediction model for racecourse starts in the Thoroughbred horse. Anim Genet 2019; 50:347-357. [PMID: 31257665 DOI: 10.1111/age.12798] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2019] [Indexed: 12/26/2022]
Abstract
Durability traits in Thoroughbred horses are heritable, economically valuable and may affect horse welfare. The aims of this study were to test the hypotheses that (i) durability traits are heritable and (ii) genetic data may be used to predict a horse's potential to have a racecourse start. Heritability for the phenotype 'number of 2- and 3-year-old starts' was estimated to be h m 2 = 0.11 ± 0.02 (n = 4499). A genome-wide association study identified SNP contributions to the trait. The neurotrimin (NTM), opioid-binding protein/cell adhesion molecule like (OPCML) and prolylcarboxypeptidase (PRCP) genes were identified as candidate genes associated with the trait. NTM functions in brain development and has been shown to have been selected during the domestication of the horse. PRCP is an established expression quantitative trait locus involved in the interaction between voluntary exercise and body composition in mice. We hypothesise that variation at these loci contributes to the motivation of the horse to exercise, which may influence its response to the demands of the training and racing environment. A random forest with mixed effects (RFME) model identified a set of SNPs that contributed to 24.7% of the heritable variation in the trait. In an independent validation set (n = 528 horses), the cohort with high genetic potential for a racecourse start had significantly fewer unraced horses (16% unraced) than did low (27% unraced) potential horses and had more favourable race outcomes among those that raced. Therefore, the information from SNPs included in the model may be used to predict horses with a greater chance of a racecourse start.
Collapse
Affiliation(s)
- B A McGivney
- Plusvital Ltd, The Highline, Dun Laoghaire Industrial Estate, Dun Laoghaire, Dublin, Ireland
| | - B Hernandez
- Prolego Scientific, Nova UCD, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland.,The Irish Longitudinal Study on Aging (TILDA), Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - L M Katz
- UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - D E MacHugh
- UCD Conway Institute for Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland.,UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - S P McGovern
- Plusvital Ltd, The Highline, Dun Laoghaire Industrial Estate, Dun Laoghaire, Dublin, Ireland
| | - A C Parnell
- Prolego Scientific, Nova UCD, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland.,School of Mathematics and Statistics, Insight Centre for Data Analytics, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| | - H L Wiencko
- Plusvital Ltd, The Highline, Dun Laoghaire Industrial Estate, Dun Laoghaire, Dublin, Ireland
| | - E W Hill
- Plusvital Ltd, The Highline, Dun Laoghaire Industrial Estate, Dun Laoghaire, Dublin, Ireland.,UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, D04 V1W8, Ireland
| |
Collapse
|
7
|
Lightfoot JT, DE Geus EJC, Booth FW, Bray MS, DEN Hoed M, Kaprio J, Kelly SA, Pomp D, Saul MC, Thomis MA, Garland T, Bouchard C. Biological/Genetic Regulation of Physical Activity Level: Consensus from GenBioPAC. Med Sci Sports Exerc 2019; 50:863-873. [PMID: 29166322 DOI: 10.1249/mss.0000000000001499] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE Physical activity unquestionably maintains and improves health; however, physical activity levels globally are low and not rising despite all the resources devoted to this goal. Attention in both the research literature and the public policy domain has focused on social-behavioral factors; however, a growing body of literature suggests that biological determinants play a significant role in regulating physical activity levels. For instance, physical activity level, measured in various manners, has a genetic component in both humans and nonhuman animal models. This consensus article, developed as a result of an American College of Sports Medicine-sponsored round table, provides a brief review of the theoretical concepts and existing literature that supports a significant role of genetic and other biological factors in the regulation of physical activity. CONCLUSIONS Future research on physical activity regulation should incorporate genetics and other biological determinants of physical activity instead of a sole reliance on social and other environmental determinants.
Collapse
Affiliation(s)
- J Timothy Lightfoot
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Eco J C DE Geus
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Frank W Booth
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Molly S Bray
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Marcel DEN Hoed
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Jaakko Kaprio
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Scott A Kelly
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Daniel Pomp
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Michael C Saul
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Martine A Thomis
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Theodore Garland
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| | - Claude Bouchard
- Department of Health and Kinesiology, Texas A&M University, College Station, TX.,Department of Health and Kinesiology, Texas A&M University, College Station, TX
| |
Collapse
|
8
|
Albert FW, Bloom JS, Siegel J, Day L, Kruglyak L. Genetics of trans-regulatory variation in gene expression. eLife 2018; 7:e35471. [PMID: 30014850 PMCID: PMC6072440 DOI: 10.7554/elife.35471] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 06/30/2018] [Indexed: 12/02/2022] Open
Abstract
Heritable variation in gene expression forms a crucial bridge between genomic variation and the biology of many traits. However, most expression quantitative trait loci (eQTLs) remain unidentified. We mapped eQTLs by transcriptome sequencing in 1012 yeast segregants. The resulting eQTLs accounted for over 70% of the heritability of mRNA levels, allowing comprehensive dissection of regulatory variation. Most genes had multiple eQTLs. Most expression variation arose from trans-acting eQTLs distant from their target genes. Nearly all trans-eQTLs clustered at 102 hotspot locations, some of which influenced the expression of thousands of genes. Fine-mapped hotspot regions were enriched for transcription factor genes. While most genes had a local eQTL, most of these had no detectable effects on the expression of other genes in trans. Hundreds of non-additive genetic interactions accounted for small fractions of expression variation. These results reveal the complexity of genetic influences on transcriptome variation in unprecedented depth and detail.
Collapse
Affiliation(s)
- Frank Wolfgang Albert
- Department of Genetics, Cell Biology and DevelopmentUniversity of MinnesotaMinneapolisUnited States
| | - Joshua S Bloom
- Department of Human GeneticsUniversity of California, Los AngelesLos AngelesUnited States
- Department of Biological ChemistryUniversity of California, Los AngelesLos AngelesUnited States
- Howard Hughes Medical InstituteLos AngelesUnited States
| | - Jake Siegel
- Department of Human GeneticsUniversity of California, Los AngelesLos AngelesUnited States
- Department of Biological ChemistryUniversity of California, Los AngelesLos AngelesUnited States
- Howard Hughes Medical InstituteLos AngelesUnited States
| | - Laura Day
- Department of Human GeneticsUniversity of California, Los AngelesLos AngelesUnited States
- Department of Biological ChemistryUniversity of California, Los AngelesLos AngelesUnited States
- Howard Hughes Medical InstituteLos AngelesUnited States
| | - Leonid Kruglyak
- Department of Human GeneticsUniversity of California, Los AngelesLos AngelesUnited States
- Department of Biological ChemistryUniversity of California, Los AngelesLos AngelesUnited States
- Howard Hughes Medical InstituteLos AngelesUnited States
| |
Collapse
|
9
|
McMullan RC, Ferris MT, Bell TA, Menachery VD, Baric RS, Hua K, Pomp D, Smith‐Ryan AE, de Villena FP. CC002/Unc females are mouse models of exercise-induced paradoxical fat response. Physiol Rep 2018; 6:e13716. [PMID: 29924460 PMCID: PMC6009762 DOI: 10.14814/phy2.13716] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 05/03/2018] [Indexed: 12/13/2022] Open
Abstract
Exercise results in beneficial health outcomes and protects against a variety of chronic diseases. However, U.S. exercise guidelines recommend identical exercise programs for everyone, despite individual variation in responses to these programs, including paradoxical fat gain. Experimental models of exercise-induced paradoxical outcomes may enable the dissection of underlying physiological mechanisms as well as the evaluation of potential interventions. Whereas several studies have identified individual mice exhibiting paradoxical fat gain following exercise, no systematic effort has been conducted to identify and characterize models of paradoxical response. Strains from the Collaborative Cross (CC) genetic reference population were used due to its high levels of genetic variation, its reproducible nature, and the observation that the CC is a rich source of novel disease models, to assess the impact genetic background has on exercise responses. We identified the strain CC002/Unc as an exercise-induced paradoxical fat response model in a controlled voluntary exercise study across multiple ages in female mice. We also found sex and genetic differences were consistent with this pattern in a study of forced exercise programs. These results provide a novel model for studies to determine the mechanisms behind paradoxical metabolic responses to exercise, and enable development of more rational personalized exercise recommendations based on factors such as age, sex, and genetic background.
Collapse
Affiliation(s)
- Rachel C. McMullan
- Department of GeneticsSchool of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
- Genetics and Molecular Biology CurriculumSchool of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
- Lineberger Comprehensive Cancer CenterUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| | - Martin T. Ferris
- Department of GeneticsSchool of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| | - Timothy A. Bell
- Department of GeneticsSchool of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
- Lineberger Comprehensive Cancer CenterUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| | - Vineet D. Menachery
- Department of EpidemiologyGillings School of Global Public HealthUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| | - Ralph S. Baric
- Department of EpidemiologyGillings School of Global Public HealthUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| | - Kunjie Hua
- Department of GeneticsSchool of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| | - Daniel Pomp
- Department of GeneticsSchool of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| | - Abbie E. Smith‐Ryan
- Department of Exercise and Sport ScienceCollege of Arts and SciencesUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| | - Fernando Pardo‐Manuel de Villena
- Department of GeneticsSchool of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
- Lineberger Comprehensive Cancer CenterUniversity of North Carolina at Chapel HillChapel HillNorth Carolina
| |
Collapse
|
10
|
Garland T, Cadney MD, Waterland RA. Early-Life Effects on Adult Physical Activity: Concepts, Relevance, and Experimental Approaches. Physiol Biochem Zool 2016; 90:1-14. [PMID: 28051947 PMCID: PMC6397655 DOI: 10.1086/689775] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Locomotion is a defining characteristic of animal life and plays a crucial role in most behaviors. Locomotion involves physical activity, which can have far-reaching effects on physiology and neurobiology, both acutely and chronically. In human populations and in laboratory rodents, higher levels of physical activity are generally associated with positive health outcomes, although excessive exercise can have adverse consequences. Whether and how such relationships occur in wild animals is unknown. Behavioral variation among individuals arises from genetic and environmental factors and their interactions as well as from developmental programming (persistent effects of early-life environment). Although tremendous progress has been made in identifying genetic and environmental influences on individual differences in behavior, early-life effects are not well understood. Early-life effects can in some cases persist across multiple generations following a single exposure and, in principle, may constrain or facilitate the rate of evolution at multiple levels of biological organization. Understanding the mechanisms of such transgenerational effects (e.g., exposure to stress hormones in utero, inherited epigenetic alterations) may prove crucial to explaining unexpected and/or sex-specific responses to selection as well as limits to adaptation. One area receiving increased attention is early-life effects on adult physical activity. Correlational data from epidemiological studies suggest that early-life nutritional stress can (adversely) affect adult human activity levels and associated physiological traits (e.g., body composition, metabolic health). The few existing studies of laboratory rodents demonstrate that both maternal and early-life exercise can affect adult levels of physical activity and related phenotypes. Going forward, rodents offer many opportunities for experimental studies of (multigenerational) early-life effects, including studies that use maternal exposures and cross-fostering designs.
Collapse
Affiliation(s)
- Theodore Garland
- Department of Biology, University of California, Riverside, California 92521
| | - Marcell D. Cadney
- Department of Biology, University of California, Riverside, California 92521
| | - Robert A. Waterland
- Departments of Pediatrics and Molecular & Human Genetics, Baylor College of Medicine, USDA/ARS Children’s Nutrition Research Center, Houston, Texas 77030
| |
Collapse
|
11
|
McMullan RC, Kelly SA, Hua K, Buckley BK, Faber JE, Pardo-Manuel de Villena F, Pomp D. Long-term exercise in mice has sex-dependent benefits on body composition and metabolism during aging. Physiol Rep 2016; 4:4/21/e13011. [PMID: 27905293 PMCID: PMC5112492 DOI: 10.14814/phy2.13011] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Accepted: 09/22/2016] [Indexed: 12/19/2022] Open
Abstract
Aging is associated with declining exercise and unhealthy changes in body composition. Exercise ameliorates certain adverse age‐related physiological changes and protects against many chronic diseases. Despite these benefits, willingness to exercise and physiological responses to exercise vary widely, and long‐term exercise and its benefits are difficult and costly to measure in humans. Furthermore, physiological effects of aging in humans are confounded with changes in lifestyle and environment. We used C57BL/6J mice to examine long‐term patterns of exercise during aging and its physiological effects in a well‐controlled environment. One‐year‐old male (n = 30) and female (n = 30) mice were divided into equal size cohorts and aged for an additional year. One cohort was given access to voluntary running wheels while another was denied exercise other than home cage movement. Body mass, composition, and metabolic traits were measured before, throughout, and after 1 year of treatment. Long‐term exercise significantly prevented gains in body mass and body fat, while preventing loss of lean mass. We observed sex‐dependent differences in body mass and composition trajectories during aging. Wheel running (distance, speed, duration) was greater in females than males and declined with age. We conclude that long‐term exercise may serve as a preventive measure against age‐related weight gain and body composition changes, and that mouse inbred strains can be used to characterize effects of long‐term exercise and factors (e.g. sex, age) modulating these effects. These findings will facilitate studies on relationships between exercise and health in aging populations, including genetic predisposition and genotype‐by‐environment interactions.
Collapse
Affiliation(s)
- Rachel C McMullan
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Scott A Kelly
- Department of Zoology, Ohio Wesleyan University, Delaware, Ohio
| | - Kunjie Hua
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Brian K Buckley
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - James E Faber
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Fernando Pardo-Manuel de Villena
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Daniel Pomp
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| |
Collapse
|
12
|
Abstract
The identification of genetic variants responsible for behavioral variation is an enduring goal in biology, with wide-scale ramifications, ranging from medical research to evolutionary theory on personality syndromes. Here, we use for the first time a large-scale genetical genomics analysis in the brains of chickens to identify genes affecting anxiety as measured by an open field test. We combine quantitative trait locus (QTL) analysis in 572 individuals and expression QTL (eQTL) analysis in 129 individuals from an advanced intercross between domestic chickens and Red Junglefowl. We identify 10 putative quantitative trait genes affecting anxiety behavior. These genes were tested for an association in the mouse Heterogeneous Stock anxiety (open field) data set and human GWAS data sets for bipolar disorder, major depressive disorder, and schizophrenia. Although comparisons between species are complex, associations were observed for four of the candidate genes in mice and three of the candidate genes in humans. Using a multimodel approach we have therefore identified a number of putative quantitative trait genes affecting anxiety behavior, principally in chickens but also with some potentially translational effects as well. This study demonstrates that chickens are an excellent model organism for the genetic dissection of behavior.
Collapse
|
13
|
Darlington TM, McCarthy RD, Cox RJ, Miyamoto-Ditmon J, Gallego X, Ehringer MA. Voluntary wheel running reduces voluntary consumption of ethanol in mice: identification of candidate genes through striatal gene expression profiling. GENES BRAIN AND BEHAVIOR 2016; 15:474-90. [PMID: 27063791 DOI: 10.1111/gbb.12294] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/11/2016] [Accepted: 04/06/2016] [Indexed: 01/10/2023]
Abstract
Hedonic substitution, where wheel running reduces voluntary ethanol consumption, has been observed in prior studies. Here, we replicate and expand on previous work showing that mice decrease voluntary ethanol consumption and preference when given access to a running wheel. While earlier work has been limited mainly to behavioral studies, here we assess the underlying molecular mechanisms that may account for this interaction. From four groups of female C57BL/6J mice (control, access to two-bottle choice ethanol, access to a running wheel, and access to both two-bottle choice ethanol and a running wheel), mRNA-sequencing of the striatum identified differential gene expression. Many genes in ethanol preference quantitative trait loci were differentially expressed due to running. Furthermore, we conducted Weighted Gene Co-expression Network Analysis and identified gene networks corresponding to each effect behavioral group. Candidate genes for mediating the behavioral interaction between ethanol consumption and wheel running include multiple potassium channel genes, Oprm1, Prkcg, Stxbp1, Crhr1, Gabra3, Slc6a13, Stx1b, Pomc, Rassf5 and Camta2. After observing an overlap of many genes and functional groups previously identified in studies of initial sensitivity to ethanol, we hypothesized that wheel running may induce a change in sensitivity, thereby affecting ethanol consumption. A behavioral study examining Loss of Righting Reflex to ethanol following exercise trended toward supporting this hypothesis. These data provide a rich resource for future studies that may better characterize the observed transcriptional changes in gene networks in response to ethanol consumption and wheel running.
Collapse
Affiliation(s)
- T M Darlington
- Institute for Behavioral Genetics, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA.,Current address: Department of Psychiatry, University of Utah, Salt Lake City, UT, USA
| | - R D McCarthy
- Institute for Behavioral Genetics, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - R J Cox
- Institute for Behavioral Genetics, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - J Miyamoto-Ditmon
- Institute for Behavioral Genetics, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - X Gallego
- Institute for Behavioral Genetics, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - M A Ehringer
- Institute for Behavioral Genetics, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| |
Collapse
|
14
|
Kohl KD, Sadowska ET, Rudolf AM, Dearing MD, Koteja P. Experimental Evolution on a Wild Mammal Species Results in Modifications of Gut Microbial Communities. Front Microbiol 2016; 7:634. [PMID: 27199960 PMCID: PMC4854874 DOI: 10.3389/fmicb.2016.00634] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/18/2016] [Indexed: 01/15/2023] Open
Abstract
Comparative studies have shown that diet, life history, and phylogeny interact to determine microbial community structure across mammalian hosts. However, these studies are often confounded by numerous factors. Selection experiments offer unique opportunities to validate conclusions and test hypotheses generated by comparative studies. We used a replicated, 15-generation selection experiment on bank voles (Myodes glareolus) that have been selected for high swim-induced aerobic metabolism, predatory behavior toward crickets, and the ability to maintain body mass on a high-fiber, herbivorous diet. We predicted that selection on host performance, mimicking adaptive radiation, would result in distinct microbial signatures. We collected foregut and cecum samples from animals that were all fed the same nutrient-rich diet and had not been subjected to any performance tests. We conducted microbial inventories of gut contents by sequencing the V4 region of the 16S rRNA gene. We found no differences in cecal microbial community structure or diversity between control lines and the aerobic or predatory lines. However, the cecal chambers of voles selected for herbivorous capability harbored distinct microbial communities that exhibited higher diversity than control lines. The foregut communities of herbivorous-selected voles were also distinct from control lines. Overall, this experiment suggests that differences in microbial communities across herbivorous mammals may be evolved, and not solely driven by current diet or other transient factors.
Collapse
Affiliation(s)
- Kevin D Kohl
- Department of Biological Sciences, Vanderbilt University Nashville, TN, USA
| | - Edyta T Sadowska
- Institute of Environmental Sciences, Jagiellonian University Kraków, Poland
| | - Agata M Rudolf
- Institute of Environmental Sciences, Jagiellonian University Kraków, Poland
| | - M Denise Dearing
- Department of Biology, University of Utah Salt Lake City, UT, USA
| | - Paweł Koteja
- Institute of Environmental Sciences, Jagiellonian University Kraków, Poland
| |
Collapse
|
15
|
Kelly SA, Villena FPMD, Pomp D. The 'Omics' of Voluntary Exercise: Systems Approaches to a Complex Phenotype. Trends Endocrinol Metab 2015; 26:673-675. [PMID: 26555601 DOI: 10.1016/j.tem.2015.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Revised: 10/15/2015] [Accepted: 10/19/2015] [Indexed: 10/22/2022]
Abstract
Predisposition to engage in exercise is highly variable and simultaneously influenced by the environment, complex genomics, and their interactions. Given the importance of exercise to health, understanding the underlying influences of variability is crucial. Here, we discuss murine systems approaches, focusing on 'omics', relevant to revealing the architecture of voluntary activity.
Collapse
Affiliation(s)
- Scott A Kelly
- Department of Zoology, Ohio Wesleyan University, Delaware, OH 43015, USA
| | - Fernando Pardo-Manuel de Villena
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Daniel Pomp
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA.
| |
Collapse
|
16
|
Acosta W, Meek TH, Schutz H, Dlugosz EM, Vu KT, Garland T. Effects of early-onset voluntary exercise on adult physical activity and associated phenotypes in mice. Physiol Behav 2015; 149:279-86. [DOI: 10.1016/j.physbeh.2015.06.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 06/10/2015] [Accepted: 06/11/2015] [Indexed: 01/15/2023]
|
17
|
Storz JF, Bridgham JT, Kelly SA, Garland T. Genetic approaches in comparative and evolutionary physiology. Am J Physiol Regul Integr Comp Physiol 2015; 309:R197-214. [PMID: 26041111 PMCID: PMC4525326 DOI: 10.1152/ajpregu.00100.2015] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 05/23/2015] [Indexed: 01/04/2023]
Abstract
Whole animal physiological performance is highly polygenic and highly plastic, and the same is generally true for the many subordinate traits that underlie performance capacities. Quantitative genetics, therefore, provides an appropriate framework for the analysis of physiological phenotypes and can be used to infer the microevolutionary processes that have shaped patterns of trait variation within and among species. In cases where specific genes are known to contribute to variation in physiological traits, analyses of intraspecific polymorphism and interspecific divergence can reveal molecular mechanisms of functional evolution and can provide insights into the possible adaptive significance of observed sequence changes. In this review, we explain how the tools and theory of quantitative genetics, population genetics, and molecular evolution can inform our understanding of mechanism and process in physiological evolution. For example, lab-based studies of polygenic inheritance can be integrated with field-based studies of trait variation and survivorship to measure selection in the wild, thereby providing direct insights into the adaptive significance of physiological variation. Analyses of quantitative genetic variation in selection experiments can be used to probe interrelationships among traits and the genetic basis of physiological trade-offs and constraints. We review approaches for characterizing the genetic architecture of physiological traits, including linkage mapping and association mapping, and systems approaches for dissecting intermediary steps in the chain of causation between genotype and phenotype. We also discuss the promise and limitations of population genomic approaches for inferring adaptation at specific loci. We end by highlighting the role of organismal physiology in the functional synthesis of evolutionary biology.
Collapse
Affiliation(s)
- Jay F Storz
- School of Biological Sciences, University of Nebraska, Lincoln, Nebraska;
| | - Jamie T Bridgham
- Institute of Ecology and Evolution, University of Oregon, Eugene, Oregon
| | - Scott A Kelly
- Department of Zoology, Ohio Wesleyan University, Delaware, Ohio; and
| | - Theodore Garland
- Department of Biology, University of California, Riverside, Riverside, California
| |
Collapse
|
18
|
Dawes M, Kochan KJ, Riggs PK, Timothy Lightfoot J. Differential miRNA expression in inherently high- and low-active inbred mice. Physiol Rep 2015; 3:3/7/e12469. [PMID: 26229004 PMCID: PMC4552544 DOI: 10.14814/phy2.12469] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 06/26/2015] [Indexed: 01/12/2023] Open
Abstract
Despite established health benefits of regular exercise, the majority of Americans do not meet the recommended levels of physical activity. While it is known that voluntary activity levels are largely heritable, the genetic mechanisms that regulate activity are not well understood. MicroRNAs (miRNAs) are small non-coding RNAs that inhibit transcription by binding to a target gene, inhibiting protein production. The purpose of this study was to investigate differential miRNA expression between inherently high- (C57L/J) and low- (C3H/HeJ) active inbred mice in soleus, extensor digitorum longus (EDL), and nucleus accumbens tissues. Expression was initially determined by miRNA microarray analysis, and selected miRNAs were validated by qRT-PCR. Expression of 13 miRNAs varied between strains in the nucleus accumbens, 20 in soleus, and eight in EDL, by microarray analysis. Two miRNAs were validated by qRT-PCR in the nucleus accumbens; miR-466 was downregulated (∼4 fold; P < 0.0004), and miR-342-5p was upregulated (∼115 fold; P < 0.0001) in high-active mice. MiR-466 was downregulated (∼5 fold; P < 0.0001) in the soleus of high-active mice as well. Interestingly, miR-466 is one of several miRNA families with sequence located in intron 10 of Sfmbt2; miRNAs at this locus are thought to drive imprinting of this gene. “Pathways in cancer” and “TGFβ signaling” were the most significant pathways of putative target genes in both the soleus and nucleus accumbens. Our results are the first to consider differential miRNA expression between high- and low-active mice, and suggest that miRNAs may play a role in regulation of physical activity.
Collapse
Affiliation(s)
- Michelle Dawes
- Department of Health and Kinesiology, Texas A&M University, College Station, Texas, USA
| | - Kelli J Kochan
- Department of Animal Science, Texas A&M University, College Station, Texas, USA
| | - Penny K Riggs
- Department of Animal Science, Texas A&M University, College Station, Texas, USA
| | - J Timothy Lightfoot
- Department of Health and Kinesiology, Texas A&M University, College Station, Texas, USA
| |
Collapse
|
19
|
Konczal M, Babik W, Radwan J, Sadowska ET, Koteja P. Initial Molecular-Level Response to Artificial Selection for Increased Aerobic Metabolism Occurs Primarily through Changes in Gene Expression. Mol Biol Evol 2015; 32:1461-73. [DOI: 10.1093/molbev/msv038] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
|
20
|
Albert FW, Kruglyak L. The role of regulatory variation in complex traits and disease. Nat Rev Genet 2015; 16:197-212. [DOI: 10.1038/nrg3891] [Citation(s) in RCA: 684] [Impact Index Per Article: 76.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
21
|
Lapointe J, Hughes B, Bigras E, Hekimi S. Compensatory elevation of voluntary activity in mouse mutants with impaired mitochondrial energy metabolism. Physiol Rep 2014; 2:2/11/e12214. [PMID: 25413331 PMCID: PMC4255820 DOI: 10.14814/phy2.12214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Mitochondria play a crucial role in determining whole‐body metabolism and exercise
capacity. Genetic mouse models of mild mitochondrial dysfunction provide an opportunity to
understand how mitochondrial function affects these parameters. MCLK1 (a.k.a. Coq7) is an enzyme
implicated in the biosynthesis of ubiquinone (UQ; Coenzyme Q). Low levels of MCLK1 in
Mclk1+/− heterozygous mutants lead to abnormal
sub‐mitochondrial distribution of UQ, impaired mitochondrial function, elevated mitochondrial
oxidative stress, and increased lifespan. Here, we report that young
Mclk1+/− males, but not females, show a significant
decrease in whole‐body metabolic rate as measured by indirect calorimetry. Such a
sex‐specific effect of mitochondrial dysfunction on energy metabolism has also been reported
for heterozygous mice carrying a mutation for the gene encoding the “Rieske” protein
of mitochondrial complex III
(RISP+/P224S). We find that both
Mclk1+/− and
RISP+/P224S males are capable of
restoring their defective metabolic rates by making significantly more voluntary use of a running
wheel compared to wild type. However, this increase in voluntary activity does not reflect their
exercise capacity, which we found to be impaired as revealed by a shorter treadmill distance run
before exhaustion. In contrast to what is observed in
Mclk1+/− and
RISP+/P224S mutants,
Sod2+/− mice with elevated oxidative stress and
major mitochondrial dysfunction did not increase voluntary activity. Our study reveals a
sex‐specific effect on how impaired mitochondrial function impacts whole‐body energy
metabolism and locomotory behavior, and contributes to the understanding of the metabolic and
behavioral consequences of mitochondrial disorders. Mitochondria play a crucial role in determining whole‐body metabolism, lifespan and
exercise capacity. This study reports sex‐specific effects of mitochondrial dysfunction,
resulting in increased spontaneous activity in response to impaired metabolic rates. These findings
contribute to the understanding of the metabolic and behavioral consequences of mitochondrial
disorders.
Collapse
Affiliation(s)
- Jérôme Lapointe
- Department of Biology, McGill University, Montréal, Quebec, Canada Agriculture and Agri-Food Canada, 2000 College St., Sherbrooke, J1M 0C8, Quebec, Canada
| | - Bryan Hughes
- Department of Biology, McGill University, Montréal, Quebec, Canada Department of Pharmacology, University of Alberta, Edmonton, T6G 2S2, Alberta, Canada
| | - Eve Bigras
- Department of Biology, McGill University, Montréal, Quebec, Canada
| | - Siegfried Hekimi
- Department of Biology, McGill University, Montréal, Quebec, Canada
| |
Collapse
|
22
|
Abstract
Interindividual differences in many behaviors are partly due to genetic differences, but the identification of the genes and variants that influence behavior remains challenging. Here, we studied an F2 intercross of two outbred lines of rats selected for tame and aggressive behavior toward humans for >64 generations. By using a mapping approach that is able to identify genetic loci segregating within the lines, we identified four times more loci influencing tameness and aggression than by an approach that assumes fixation of causative alleles, suggesting that many causative loci were not driven to fixation by the selection. We used RNA sequencing in 150 F2 animals to identify hundreds of loci that influence brain gene expression. Several of these loci colocalize with tameness loci and may reflect the same genetic variants. Through analyses of correlations between allele effects on behavior and gene expression, differential expression between the tame and aggressive rat selection lines, and correlations between gene expression and tameness in F2 animals, we identify the genes Gltscr2, Lgi4, Zfp40, and Slc17a7 as candidate contributors to the strikingly different behavior of the tame and aggressive animals.
Collapse
|
23
|
Kelly SA, Nehrenberg DL, Hua K, Garland T, Pomp D. Quantitative genomics of voluntary exercise in mice: transcriptional analysis and mapping of expression QTL in muscle. Physiol Genomics 2014; 46:593-601. [PMID: 24939925 DOI: 10.1152/physiolgenomics.00023.2014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Motivation and ability both underlie voluntary exercise, each with a potentially unique genetic architecture. Muscle structure and function are one of many morphological and physiological systems acting to simultaneously determine exercise ability. We generated a large (n = 815) advanced intercross line of mice (G4) derived from a line selectively bred for increased wheel running (high runner) and the C57BL/6J inbred strain. We previously mapped quantitative trait loci (QTL) contributing to voluntary exercise, body composition, and changes in body composition as a result of exercise. Using brain tissue in a subset of the G4 (n = 244), we have also previously reported expression QTL (eQTL) colocalizing with the QTL for the higher-level phenotypes. Here, we examined the transcriptional landscape of hind limb muscle tissue via global mRNA expression profiles. Correlations revealed an ∼1,168% increase in significant relationships between muscle transcript expression levels and the same exercise and body composition phenotypes examined previously in the brain. The exercise trait most often significantly correlated with gene expression in the brain was running duration while in the muscle it was maximum running speed. This difference may indicate that time spent engaging in exercise behavior may be more influenced by central (neurobiological) mechanisms, while intensity of exercise may be largely controlled by peripheral mechanisms. Additionally, we used subsets of cis-acting eQTL, colocalizing with QTL, to identify candidate genes based on both positional and functional evidence. We discuss three plausible candidate genes (Insig2, Prcp, Sparc) and their potential regulatory role.
Collapse
Affiliation(s)
- Scott A Kelly
- Department of Zoology, Ohio Wesleyan University, Delaware, Ohio;
| | - Derrick L Nehrenberg
- Department of Genetics, University of North Carolina, Chapel Hill, North Carolina; and
| | - Kunjie Hua
- Department of Genetics, University of North Carolina, Chapel Hill, North Carolina; and
| | - Theodore Garland
- Department of Biology, University of California, Riverside, Riverside, California
| | - Daniel Pomp
- Department of Genetics, University of North Carolina, Chapel Hill, North Carolina; and
| |
Collapse
|
24
|
Gonzales NM, Palmer AA. Fine-mapping QTLs in advanced intercross lines and other outbred populations. Mamm Genome 2014; 25:271-92. [PMID: 24906874 DOI: 10.1007/s00335-014-9523-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 04/25/2014] [Indexed: 12/16/2022]
Abstract
Quantitative genetic studies in model organisms, particularly in mice, have been extremely successful in identifying chromosomal regions that are associated with a wide variety of behavioral and other traits. However, it is now widely understood that identification of the underlying genes will be far more challenging. In the last few years, a variety of populations have been utilized in an effort to more finely map these chromosomal regions with the goal of identifying specific genes. The common property of these newer populations is that linkage disequilibrium spans relatively short distances, which permits fine-scale mapping resolution. This review focuses on advanced intercross lines (AILs) which are the simplest such population. As originally proposed in 1995 by Darvasi and Soller, an AIL is the product of intercrossing two inbred strains beyond the F2 generation. Unlike recombinant inbred strains, AILs are maintained as outbred populations; brother-sister matings are specifically avoided. Each generation of intercrossing beyond the F2 further degrades linkage disequilibrium between adjacent makers, which allows for fine-scale mapping of quantitative trait loci (QTLs). Advances in genotyping technology and techniques for the statistical analysis of AILs have permitted rapid advances in the application of AILs. We review some of the analytical issues and available software, including QTLRel, EMMA, EMMAX, GEMMA, TASSEL, GRAMMAR, WOMBAT, Mendel, and others.
Collapse
Affiliation(s)
- Natalia M Gonzales
- Department of Human Genetics, University of Chicago, Chicago, IL, 60637, USA
| | | |
Collapse
|
25
|
Ferguson DP, Dangott LJ, Schmitt EE, Vellers HL, Lightfoot JT. Differential skeletal muscle proteome of high- and low-active mice. J Appl Physiol (1985) 2014; 116:1057-67. [PMID: 24505100 DOI: 10.1152/japplphysiol.00911.2013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Physical inactivity contributes to cardiovascular disease, type II diabetes, obesity, and some types of cancer. While the literature is clear that there is genetic regulation of physical activity with existing gene knockout data suggesting that skeletal muscle mechanisms contribute to the regulation of activity, actual differences in end-protein expression between high- and low-active mice have not been investigated. This study used two-dimensional differential gel electrophoresis coupled with mass spectrometry to evaluate the proteomic differences between high-active (C57L/J) and low-active (C3H/HeJ) mice in the soleus and extensor digitorum longus (EDL). Furthermore, vivo-morpholinos were used to transiently knockdown candidate proteins to confirm their involvement in physical activity regulation. Proteins with higher expression patterns generally fell into the calcium-regulating and Krebs (TCA) cycle pathways in the high-active mice (e.g., annexin A6, P = 0.0031; calsequestrin 1; P = 0.000025), while the overexpressed proteins in the low-active mice generally fell into cytoskeletal structure- and electron transport chain-related pathways (e.g., ATPase, P = 0.031; NADH dehydrogenase, P = 0.027). Transient knockdown of annexin A6 and calsequestrin 1 protein of high-active mice with vivo-morpholinos resulted in decreased physical activity levels (P = 0.001). These data suggest that high- and low-active mice have unique protein expression patterns and that each pattern contributes to the peripheral capability to be either high- or low-active, suggesting that different specific mechanisms regulate activity leading to the high- or low-activity status of the animal.
Collapse
Affiliation(s)
- David P Ferguson
- Children's Nutritional Research Center, Baylor College of Medicine, Houston, Texas
| | | | | | | | | |
Collapse
|
26
|
Herring MP, Sailors MH, Bray MS. Genetic factors in exercise adoption, adherence and obesity. Obes Rev 2014; 15:29-39. [PMID: 24034448 DOI: 10.1111/obr.12089] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 06/26/2013] [Accepted: 08/05/2013] [Indexed: 01/09/2023]
Abstract
Physical activity and exercise play critical roles in energy balance. While many interventions targeted at increasing physical activity have demonstrated efficacy in promoting weight loss or maintenance in the short term, long term adherence to such programmes is not frequently observed. Numerous factors have been examined for their ability to predict and/or influence physical activity and exercise adherence. Although physical activity has been demonstrated to have a strong genetic component in both animals and humans, few studies have examined the association between genetic variation and exercise adherence. In this review, we provide a detailed overview of the non-genetic and genetic predictors of physical activity and adherence to exercise. In addition, we report the results of analysis of 26 single nucleotide polymorphisms in six candidate genes examined for association to exercise adherence, duration, intensity and total exercise dose in young adults from the Training Interventions and Genetics of Exercise Response (TIGER) Study. Based on both animal and human research, neural signalling and pleasure/reward systems in the brain may drive in large part the propensity to be physically active and to adhere to an exercise programme. Adherence/compliance research in other fields may inform future investigation of the genetics of exercise adherence.
Collapse
Affiliation(s)
- M P Herring
- Department of Epidemiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | | | | |
Collapse
|
27
|
Kelly SA, Pomp D. Genetic determinants of voluntary exercise. Trends Genet 2013; 29:348-57. [PMID: 23351966 PMCID: PMC3665695 DOI: 10.1016/j.tig.2012.12.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 12/06/2012] [Accepted: 12/20/2012] [Indexed: 12/17/2022]
Abstract
Variation in voluntary exercise behavior is an important determinant of long-term human health. Increased physical activity is used as a preventative measure or therapeutic intervention for disease, and a sedentary lifestyle has generally been viewed as unhealthy. Predisposition to engage in voluntary activity is heritable and induces protective metabolic changes, but its complex genetic/genomic architecture has only recently begun to emerge. We first present a brief historical perspective and summary of the known benefits of voluntary exercise. Second, we describe human and mouse model studies using genomic and transcriptomic approaches to reveal the genetic architecture of exercise. Third, we discuss the merging of genomic information and physiological observations, revealing systems and networks that lead to a more complete mechanistic understanding of how exercise protects against disease pathogenesis. Finally, we explore potential regulation of physical activity through epigenetic mechanisms, including those that persist across multiple generations.
Collapse
Affiliation(s)
- Scott A Kelly
- Department of Zoology, Ohio Wesleyan University, Delaware, OH 43015, USA
| | | |
Collapse
|
28
|
Pistilli EE, Guo G, Stauber WT. IL-15Rα deficiency leads to mitochondrial and myofiber differences in fast mouse muscles. Cytokine 2012; 61:41-5. [PMID: 23116661 DOI: 10.1016/j.cyto.2012.09.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 09/06/2012] [Accepted: 09/25/2012] [Indexed: 12/21/2022]
Abstract
The purpose of this study was to determine mitochondrial changes in fast muscles from interleukin-15 receptor alpha knockout (IL-15RαKO) mice. We tested the hypothesis that fast muscles from IL-15RαKO mice would have a greater mitochondrial density and altered internal structure compared to muscles from control mice. In fast muscles from IL-15RαKO mice, mitochondrial density was 48% greater with a corresponding increase in mitochondrial DNA content. Although there were no differences in the relative size of isolated mitochondria, internal complexity was lower in mitochondria from IL-15RαKO mice. These data support an increase in mitochondrial biogenesis and provide direct evidence for a greater density and altered internal structure of mitochondria in EDL muscles deficient in IL-15Rα.
Collapse
Affiliation(s)
- Emidio E Pistilli
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, USA.
| | | | | |
Collapse
|