Medda S, von Deimling O, Swank R T
Biochem Genet. 1986 Apr;24(3-4):229-43. doi: 10.1007/BF00502791.
Recent experiments have demonstrated that egasyn not only sequesters beta-glucuronidase in microsomes by forming high molecular weight complexes with beta-glucuronidase, but also has carboxyl esterase activity. We have found several new phenotypes of egasyn-esterase after electrophoresis and isoelectric focusing of liver homogenates and purified egasyn of inbred and wild mouse strains. Several phenotypes corresponded in relative mobility and relative isoelectric point among inbred strains to that recently reported for esterase-22 by Eisenhardt and von Deimling [(1982). Comp. Biochem. Physiol. 73B:719]. This genetic evidence, plus a wide variety of comparative biochemical and physiological data, indicates that egasyn is identical to esterase-22. Both parental types of egasyn isozymes are expressed in heterozygous F1 progeny, suggesting that alterations in the egasyn structural gene are responsible for the altered isoelectric points. Also, egasyn is a monomer since no new esterase bands appear in F1 progeny. The variants in isoelectric point of egasyn map at or near the egasyn (Eg) gene within the esterases of cluster 1 near Es-9 on chromosome 8.
最近的实验表明，egasyn不仅通过与β-葡萄糖醛酸酶形成高分子量复合物而将其隔离在微粒体中，而且还具有羧酸酯酶活性。我们在近交系和野生小鼠品系的肝脏匀浆和纯化的egasyn进行电泳和等电聚焦后，发现了egasyn酯酶的几种新表型。近交系中几种表型的相对迁移率和相对等电点与艾森哈特和冯·戴姆林最近报道的酯酶-22的相对迁移率和相对等电点[(1982年)。《比较生物化学与生理学》73B:719]。这一遗传学证据，加上各种各样的比较生化和生理学数据，表明egasyn与酯酶-22相同。egasyn同工酶的两种亲本类型在杂合F1后代中均有表达，这表明egasyn结构基因的改变是等电点改变的原因。此外，egasyn是一种单体，因为在F1后代中没有出现新的酯酶条带。egasyn等电点的变异位于8号染色体上Es-9附近的第1簇酯酶中的egasyn (Eg)基因处或附近。
