Increased contractile activity decreases RNA-protein interaction in the 3'-UTR of cytochrome c mRNA.
This study was designed to gain an insight into mechanisms by which cytochrome c gene expression is enhanced by increased contractile activity in skeletal muscle. When rat tibialis anterior muscles were stimulated (10 Hz, 0.25 ms) for 0, 2, 6, 12, or 24 h or 2, 5, 9, or 13 days (n = 4 for each time point), cytochrome c protein (enzyme-linked immunosorbent assay) and mRNA (Northern blot analysis) concentrations started to increase by 9 days, and this was associated with concurrent decreases in cytochrome c mRNA-protein interaction (RNA gel mobility shift assay). We found that the decreased RNA-protein interaction in the stimulated muscle extract was restored by ultracentrifugation (150,000 g, 1 h) in the supernatant fraction. The 150,000 g pellet fraction of stimulated muscle was capable of inhibiting the RNA-protein interaction in control tibialis anterior muscles. These results provide evidence of an inhibitory factor that is responsible for decreasing RNA-protein interaction in the 3'-untranslated region of cytochrome c mRNA in continuously stimulated muscle.
Department of Integrative Biology, University of Texas Medical School, Houston 77225, USA.
Z
Z
Yan
S
S
Salmons
Y I
YI
Dang
M T
MT
Hamilton
F W
FW
Booth
D000818:Animals; D001483:Base Sequence; D003574:Cytochrome c Group / Q000235:genetics*; D004558:Electric Stimulation; D005260:Female; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000378:metabolism*; D009841:Oligonucleotides / Q000737:chemistry; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D003574:Cytochrome c Group; D009841:Oligonucleotides; D012333:RNA, Messenger; D016601:RNA-Binding Proteins