ABSTRACT

The fact that acetyl CoA carboxylase has a dual role in metabolism is important in terms of potential dietary/hormonal regulation of the enzyme. This chapter discusses the time-dependent adaptive mechanisms which regulate acetyl CoA carboxylase activity and thus lipogenesis. The two hormones most closely associated with changes in dietary carbohydrate level, insulin and glucagon, have opposing effects on lipogenesis and the activity of acetyl CoA carboxylase in isolated rat hepatocytes. The gene for acetyl CoA carboxylase has been shown to be present in human genetic material, reportedly located on chromosome 17. The use of a c-DNA probe to study rat acetyl CoA carboxylase mRNA has showed that the transcriptional process and its regulation are far from simple. Although it is clear that there are multiple forms of acetyl CoA carboxylase mRNA in tissue, much work remains to be done before the physiological relevance of them can be understood.