López-Casillas F, Pape M E, Bai D H, Kuhn D N, Dixon J E, Kim K H
Arch Biochem Biophys. 1987 Aug 15;257(1):63-8. doi: 10.1016/0003-9861(87)90543-1.
Poly(A)+ RNA from lactating rat mammary glands was fractionated according to size by isokinetic sucrose gradient centrifugation to obtain a fraction enriched for acetyl-CoA carboxylase. In vitro translation of this RNA preparation yielded apparent full-length acetyl-CoA carboxylase with a molecular weight of 260,000. The synthesized protein was identified as acetyl-CoA carboxylase by specific immunoprecipitation. Tests with antiserum to fatty acid synthetase, revealed that the fractions containing acetyl-CoA carboxylase mRNA also contained mRNA for fatty acid synthetase; both of these mRNAs were approximately 10 kb. Fatty acid synthetase with a molecular weight of 250,000 was synthesized. Using an in vitro rabbit reticulocyte lysate translation system, we have shown that the amount of translatable acetyl-CoA carboxylase mRNA increases during lactation. On the fifth day postpartum the level of translatable acetyl-CoA carboxylase mRNA increased to a peak level seven times that on the day of parturition.
通过等速蔗糖梯度离心，根据大小对来自泌乳大鼠乳腺的聚腺苷酸加尾（Poly(A)+）RNA进行分级分离，以获得富含乙酰辅酶A羧化酶的级分。对该RNA制剂进行体外翻译，产生了分子量为260,000的明显全长乙酰辅酶A羧化酶。通过特异性免疫沉淀将合成的蛋白质鉴定为乙酰辅酶A羧化酶。用脂肪酸合成酶抗血清进行检测，结果显示含有乙酰辅酶A羧化酶mRNA的级分也含有脂肪酸合成酶的mRNA；这两种mRNA大小均约为10 kb。合成了分子量为250,000的脂肪酸合成酶。使用体外兔网织红细胞裂解物翻译系统，我们发现泌乳期间可翻译的乙酰辅酶A羧化酶mRNA的量增加。产后第五天，可翻译的乙酰辅酶A羧化酶mRNA水平增加到峰值，是分娩当天的七倍。
