Stearoyl-CoA desaturase (SCD) is the rate-limiting enzyme catalyzing the synthesis of monounsaturated fatty acids, mainly oleate (18:1) and palmitoleate (16:1). These represent the major monounsaturated fatty acids of membrane phospholipids, triglycerides, wax esters and cholesterol esters. The ratio of saturated to monounsaturated fatty acids affects phospholipid composition and alteration in this ratio has been implicated in a variety of disease states including cardiovascular disease, obesity, diabetes, neurological disease, and cancer. For this reason, the expression of SCD is of physiological significance in both normal and disease states. Several SCD gene isoforms (SCD1, SCD2, SCD3) exist in the mouse and one SCD isoform that is highly homologous to the mouse SCD1 is well characterized in human. The physiological role of each SCD isoform and the reason for having three or more SCD gene isoforms in the rodent genome are currently unknown but could be related the substrate specificities of the isomers and their regulation through tissue-specific expression. The recent studies of asebia mouse strains that have a natural mutation in the SCD1 gene and a mouse model with a targeted disruption of the SCD1 gene have provided clues concerning the role that SCD1 and its endogenous products play in the regulation of metabolism.

中文翻译：

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硬脂酰辅酶A去饱和酶的调节及其在代谢中的作用。

硬脂酰辅酶A去饱和酶（SCD）是催化单不饱和脂肪酸（主要是油酸酯（18：1）和棕榈油酸酯（16：1））合成的限速酶。这些代表膜磷脂，甘油三酸酯，蜡酯和胆固醇酯的主要单不饱和脂肪酸。饱和脂肪酸与单不饱和脂肪酸的比例影响磷脂的组成，并且该比例的改变与多种疾病有关，包括心血管疾病，肥胖症，糖尿病，神经系统疾病和癌症。因此，SCD的表达在正常和疾病状态下均具有生理意义。小鼠中存在几种SCD基因同工型（SCD1，SCD2，SCD3），并且与人SCD1高度同源的一种SCD同工型已在人类中得到了很好的表征。目前尚不清楚每种SCD同工型的生理作用以及在啮齿动物基因组中具有三个或更多SCD基因同工型的原因，但可能与异构体的底物特异性及其通过组织特异性表达的调控有关。对在SCD1基因中具有自然突变的阿斯比亚小鼠品系和靶向破坏SCD1基因的小鼠模型的最新研究提供了有关SCD1及其内源性产物在代谢调节中所起作用的线索。