Differential expression of candidate genes associated with voluntary physical activity levels in inbred mice

Abstract

This study investigated the levels of gene expression for eight potential candidate genes speculated to play a role in voluntary physical activity: Leptin Receptor (Lepr), Actinin alpha 2 (Actn), Myostatin (Mstn), Calsequestrin1 (Casq1), Dopamine Receptor 1 (Drd1), Nescient helix loop helix 2 (Nhlh2), and Glucose Transporter member 4 (Slc2a4) in soleus and nucleus accumbens of high active (C57L/J, n=3) and low active (C3H/HeJ, n=4) inbred mice as well as high (n=16) and low active (n=18) F2 offspring. All animal procedures were conducted in conformance with the FASEB Statement of Principles for the use of animals in research and education. The F2 cohort was used as a control to remove gene expression due to the homozygosity of the inbred animals. mRNA was isolated and quantitative real‐time PCR was performed. Gene expression was calculated as a ratio of the cross point (ct) of the target gene to RN18S (control gene). Mstn (p=0.02) and Casq1 (p=0.04) had higher expression in the soleus of low active animals. Mstn was also found to be differentially expressed in soleus between the high and low active F2 animals (p=.045), as well as between the progenitors (p=.03), when the groups were analyzed separately. While other genes may also regulate activity, none appear to function by differences in transcriptional product as do Mstn and Casq1 in this study. This work is supported by Texas A&M University.