title: Differential gene expression in high- and low-active inbred mice.
abstract: Numerous candidate genes have been suggested in the recent literature with proposed roles in regulation of voluntary physical activity, with little evidence of these genes' functional roles. This study compared the haplotype structure and expression profile in skeletal muscle and brain of inherently high- (C57L/J) and low- (C3H/HeJ) active mice. Expression of nine candidate genes [Actn2, Actn3, Casq1, Drd2, Lepr, Mc4r, Mstn, Papss2, and Glut4 (a.k.a. Slc2a4)] was evaluated via RT-qPCR. SNPs were observed in regions of Actn2, Casq1, Drd2, Lepr, and Papss2; however, no SNPs were located in coding sequences or associated with any known regulatory sequences. In mice exposed to a running wheel, Casq1 (P = 0.0003) and Mstn (P = 0.002) transcript levels in the soleus were higher in the low-active mice. However, when these genes were evaluated in naïve animals, differential expression was not observed, demonstrating a training effect. Among naïve mice, no genes in either tissue exhibited differential expression between strains. Considering that no obvious SNP mechanisms were determined or differential expression was observed, our results indicate that genomic structural variation or gene expression data alone is not adequate to establish any of these genes' candidacy or causality in relation to regulation of physical activity.
authors.affiliation: Department of Health and Kinesiology, Texas A&M University, College Station, TX 77843, USA ; Sydney and JL Huffines Institute for Sports Medicine and Human Performance, Texas A&M University, College Station, TX 77843, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Dawes
authors.affiliation: Department of Kinesiology, University of North Carolina Charlotte, Charlotte, NC 28223, USA.
authors.forename: Trudy
authors.initials: T
authors.lastname: Moore-Harrison
authors.affiliation: Department of Kinesiology, University of North Carolina Charlotte, Charlotte, NC 28223, USA.
authors.forename: Alicia T
authors.initials: AT
authors.lastname: Hamilton
authors.affiliation: Department of Kinesiology, University of North Carolina Charlotte, Charlotte, NC 28223, USA.
authors.forename: Tyrone
authors.initials: T
authors.lastname: Ceaser
authors.affiliation: Department of Animal Science, Texas A&M University, College Station, TX 77843, USA.
authors.forename: Kelli J
authors.initials: KJ
authors.lastname: Kochan
authors.affiliation: Department of Animal Science, Texas A&M University, College Station, TX 77843, USA.
authors.forename: Penny K
authors.initials: PK
authors.lastname: Riggs
authors.affiliation: Department of Health and Kinesiology, Texas A&M University, College Station, TX 77843, USA ; Sydney and JL Huffines Institute for Sports Medicine and Human Performance, Texas A&M University, College Station, TX 77843, USA ; Department of Kinesiology, University of North Carolina Charlotte, Charlotte, NC 28223, USA.
authors.forename: J Timothy
authors.initials: JT
authors.lastname: Lightfoot
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006239:Haplotypes; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000235:genetics*; D018482:Muscle, Skeletal / Q000378:metabolism*; D020641:Polymorphism, Single Nucleotide