Alexis S D, Young V R, Gill D M
Biochem J. 1974 Jul;142(1):185-8. doi: 10.1042/bj1420185.
Rat skeletal-muscle elongation factor 2 was assayed by causing it to react with NAD(+) by using fragment A of diphtheria toxin as the catalyst. Dietary protein restriction decreased the concentration of elongation factor 2 in homogenates of whole muscle. These decreases paralleled a decline in muscle RNA so that the number of molecules of elongation factor 2 per ribosome appeared to be independent of the diet. We conclude that elongation factor 2 is probably not the factor limiting the rate of muscle protein synthesis and is not responsible for the fall in the protein-synthetic rate in vivo observed in the muscles of animals whose dietary protein intake is inadequate.
通过使用白喉毒素片段A作为催化剂，使大鼠骨骼肌延伸因子2与NAD(+)反应，对其进行测定。饮食蛋白质限制降低了全肌肉匀浆中延伸因子2的浓度。这些降低与肌肉RNA的下降平行，因此每个核糖体上延伸因子2的分子数似乎与饮食无关。我们得出结论，延伸因子2可能不是限制肌肉蛋白质合成速率的因素，也不是饮食蛋白质摄入不足的动物肌肉中观察到的体内蛋白质合成速率下降的原因。
