Thibodeau L, Verly W G
Eur J Biochem. 1980 Jun;107(2):555-63. doi: 10.1111/j.1432-1033.1980.tb06063.x.
A method has been developed to purify rat liver nuclei; the isolated nuclei keep both nuclear membranes and retain more than 90% of the cell apurinic/apyrimidinic (AP) endodeoxyribonuclease activity. The nuclear enzyme is located mostly in chromatin non-histones; there is also an important amount of activity in the nuclear sap and some in the nuclear membranes. The cytoplasmic AP endodeoxyribonuclease activity is shared between mitochondria, cytosol and membranes. Different cell compartments appear to contain different AP endodeoxyribonuclease species: the membrane enzyme is activated by Triton whereas the other enzymes are rather inhibited; the nuclear sap enzyme has a higher molecular weight and a higher thermal resistance than the chromatin enzyme. A hypothesis is formulated according to which: (1) the chromatin enzyme is the only species important for nuclear DNA repair; (2) the species present in the other cell compartments might be precursors of the chromatin AP endodeoxyribonuclease.
已开发出一种纯化大鼠肝细胞核的方法；分离出的细胞核保留了核膜，并保留了超过90%的细胞无嘌呤/无嘧啶（AP）内切脱氧核糖核酸酶活性。核酶主要位于染色质非组蛋白中；核液中也有大量活性，核膜中也有一些活性。细胞质AP内切脱氧核糖核酸酶活性分布在线粒体、胞质溶胶和膜之间。不同的细胞区室似乎含有不同种类的AP内切脱氧核糖核酸酶：膜酶被 Triton 激活，而其他酶则受到抑制；核液酶比染色质酶具有更高的分子量和更高的热稳定性。据此提出一个假设：（1）染色质酶是对核DNA修复唯一重要的种类；（2）存在于其他细胞区室中的种类可能是染色质AP内切脱氧核糖核酸酶的前体。
