Stimulation of actin and myosin synthesis in rat gastrocnemius muscle by clenbuterol; evidence for translational control.
1. A transient rise in fractional rates of protein and actomyosin synthesis was observed in gastrocnemius muscles of rats fed clenbuterol for 1-2 days but the muscle RNA:protein ratio was unchanged, therefore protein synthesis per unit RNA (kRNA) also increased. 2. Myosin heavy and light chains and actin showed increased incorporation of [3H]phenylalanine at 2 days; these changes were proportional to increases in total protein synthesis. 3. The ratios actin mRNA:18S RNA and fast myosin heavy chain mRNA:18S RNA were unaffected by clenbuterol. 4. The data suggest that the clenbuterol-induced increase in muscle protein synthesis involves both translational control and increased tissue RNA.
Hesketh
J E
JE
Rowett Research Institute, Bucksburn, Aberdeen, U.K.
Campbell
G P
GP
Lobley
G E
GE
Maltin
C A
CA
Acamovic
F
F
Palmer
R M
RM
D000199:Actins / Q000096:biosynthesis* / Q000302:isolation & purification; D000818:Animals; D002976:Clenbuterol / Q000494:pharmacology*; D008297:Male; D009132:Muscles / Q000187:drug effects* / Q000378:metabolism; D009218:Myosins / Q000096:biosynthesis* / Q000302:isolation & purification; D009693:Nucleic Acid Hybridization; D014176:Protein Biosynthesis / Q000187:drug effects*; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats
D000199:Actins; D012333:RNA, Messenger; D012313:RNA; D009218:Myosins; D002976:Clenbuterol