Differential effects of two period genes on the physiology and proteomic profiles of mouse anterior tibialis muscles.
The molecular components that generate and maintain circadian rhythms of physiology and behavior in mammals are present both in the brain (suprachiasmatic nucleus; SCN) and in peripheral tissues. Examination of mice with targeted disruptions of either mPer1 or mPer2 has shown that these two genes have key roles in the SCN circadian clock. Here we show that loss of the clock gene mPer2 affects forced locomotor performance in mice without altering muscle contractility. A proteomic analysis revealed that the anterior tibialis muscles of the mPer2 knockout mice had higher levels of glycolytic enzymes such as triose phosphate isomerase and enolase than those of either the wild type or mPer1 knockout mice. In addition, the level of expression of HSP90 in the mPer2 mutant mice was also significantly higher than in wildtype mice. These results suggest that the reduced locomotor endurance of the mPer2 knockout mice reflects a greater dependence on anaerobic metabolism under stress conditions, and that the two canonical clock genes, mPer1 and mPer2, play distinct roles in the physiology of skeletal muscle.
Bae
Kiho
K
Department of Life Science, Yonsei University, Wonju 220-710, Korea. kbae@yonsei.ac.kr
Lee
Kisoo
K
Seo
Younguk
Y
Lee
Haesang
H
Kim
Dongyong
D
Choi
Inho
I
D000818:Animals; D001683:Biological Clocks; D001798:Blood Proteins / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics*; D002940:Circadian Rhythm; D003285:Contractile Proteins / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D006360:Heat-Shock Proteins / Q000378:metabolism; D015151:Immunoblotting; D051379:Mice; D008815:Mice, Inbred Strains; D018345:Mice, Knockout; D009043:Motor Activity; D009119:Muscle Contraction; D009124:Muscle Proteins / Q000378:metabolism; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000737:chemistry / Q000502:physiology*; D009687:Nuclear Proteins / Q000235:genetics*; D056950:Period Circadian Proteins; D040901:Proteomics; D014157:Transcription Factors / Q000235:genetics*
D001798:Blood Proteins; D018797:Cell Cycle Proteins; D003285:Contractile Proteins; D006360:Heat-Shock Proteins; D009124:Muscle Proteins; D009687:Nuclear Proteins; C539023:Per1 protein, mouse; C513312:Per2 protein, mouse; D056950:Period Circadian Proteins; D014157:Transcription Factors