[en] 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.
Disciplines :
Human health sciences: Multidisciplinary, general & others
Author, co-author :
Thibodeau, Lise; Laboratoire de Biochimie, Faculté Des Sciences, Université de Liegé, Institut de Chimie, Université de Liegè Au Sart-Tilman, Liège, 8-4000, Belgium
Verly, Walter ; Relations académiques et scientifiques (Sciences)
Language :
English
Title :
Cellular localization of the apurinic/apyrimidinic endodeoxyribonucleases in rat liver.
Alternative titles :
[fr] Localisation cellulaire des endodésoxyribonucléases apuriniques/apyrimidiniques dans le foie de rat.
