Low translational efficiency of the F1-ATPase beta-subunit mRNA largely accounts for the decreased ATPase content in brown adipose tissue mitochondria.
The half-life of the F1-ATPase beta-subunit (F1-beta) mRNA in ATPase-poor brown adipose tissue (BAT) (t1/2 = 9.5 h) was found to be 3-7-fold shorter than in liver (t1/2 = 27 h) and heart (t1/2 = 63 h) of mice. When translated in reticulocyte lysate, a 2-3-fold lower efficiency appeared with F1-beta mRNA from BAT than from other tissues. The in vitro synthesized F1-beta protein precursors of BAT, liver and heart origin were imported and processed by mouse liver mitochondria with equal efficiency. The results indicate that the pool of abundant F1-beta mRNA in BAT is not fully translatable, most likely due to its low metabolic stability.
Tvrdík
P
P
Institute of Physiology, Czechoslovak Academy of Sciences, Prague.
Kuzela
S
S
Houstĕk
J
J
D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D002001:Adipose Tissue, Brown / Q000201:enzymology*; D000818:Animals; D015152:Blotting, Northern; D051379:Mice; D008807:Mice, Inbred BALB C; D008928:Mitochondria / Q000201:enzymology*; D008930:Mitochondria, Liver / Q000201:enzymology; D009206:Myocardium / Q000201:enzymology; D014176:Protein Biosynthesis; D011498:Protein Precursors / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D006180:Proton-Translocating ATPases / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*
D011498:Protein Precursors; D012333:RNA, Messenger; D000251:Adenosine Triphosphatases; D006180:Proton-Translocating ATPases