Heesom K J, Moule S K, Denton R M
Department of Biochemistry, School of Medical Sciences, University of Bristol, UK.
FEBS Lett. 1998 Jan 23;422(1):43-6. doi: 10.1016/s0014-5793(97)01597-4.
An insulin-stimulated protein kinase specific for acetyl-CoA carboxylase has been purified from rat epididymal adipose tissue using Mono-Q chromatography. The kinase binds to (and phosphorylates) the relatively inactive, dimeric form of acetyl-CoA carboxylase, but not to its active, polymeric form, and this property has been used to purify the kinase. Under the conditions used, phosphorylation by the purified kinase did not result in a detectable increase in acetyl-CoA carboxylase activity. These studies also led to the recognition of an 'activator' protein which is capable of increasing the activity of acetyl-CoA carboxylase without changing its phosphorylation state. It is suggested that this 'activator' protein, together with the insulin-activated acetyl-CoA carboxylase kinase, may play a role in the activation of acetyl-CoA carboxylase by insulin.
利用Mono-Q色谱法从大鼠附睾脂肪组织中纯化出一种对乙酰辅酶A羧化酶具有特异性的胰岛素刺激蛋白激酶。该激酶与相对无活性的二聚体形式的乙酰辅酶A羧化酶结合（并使其磷酸化），但不与其活性聚合物形式结合，这一特性已被用于纯化该激酶。在所使用的条件下，纯化后的激酶进行的磷酸化并未导致乙酰辅酶A羧化酶活性出现可检测到的增加。这些研究还促成了一种“激活剂”蛋白的发现，该蛋白能够在不改变其磷酸化状态的情况下增加乙酰辅酶A羧化酶的活性。有人提出，这种“激活剂”蛋白与胰岛素激活的乙酰辅酶A羧化酶激酶一起，可能在胰岛素对乙酰辅酶A羧化酶的激活过程中发挥作用。
