Kim T S, Leahy P, Freake H C
Department of Nutritional Sciences, University of Connecticut, Storrs 06269-4017, USA.
Biochem Biophys Res Commun. 1996 Aug 14;225(2):647-53. doi: 10.1006/bbrc.1996.1224.
The acetyl-CoA carboxylase gene contains two promoters, PI and PII which generate multiple mRNA forms. We have used the reverse transcription-polymerase chain reaction to investigate tissue specific promoter usage in rats either fed a standard chow diet, starved for 48 h, or starved and then refed a high carbohydrate, low fat diet. Expression of PII-generated mRNAs was seen in all tissues examined and was not dramatically changed by food removal or refeeding. PI-generated mRNAs were expressed at variable levels in a narrower range of tissues and were regulated by these dietary manipulations. Thus only the PI promoter is responsive to diet and the ability of a tissue to use this promoter determines whether it can alter fatty acid synthesis in response to nutritional challenges.
乙酰辅酶A羧化酶基因包含两个启动子，PI和PII，它们可产生多种mRNA形式。我们利用逆转录-聚合酶链反应来研究正常饮食、饥饿48小时或饥饿后再喂食高碳水化合物、低脂肪饮食的大鼠中组织特异性启动子的使用情况。在所有检测的组织中均可见由PII产生的mRNA的表达，并且食物去除或再喂食对其表达没有显著影响。由PI产生的mRNA在较窄范围的组织中以可变水平表达，并受这些饮食操作的调节。因此，只有PI启动子对饮食有反应，并且组织使用该启动子的能力决定了它是否能够响应营养挑战而改变脂肪酸合成。
