Chemically reactive systems migration from

A new need in this field is to ascertain the contribution of the nuclear P-450 enzyme systems to mutagenesis and carcinogenesis. The finding that a complete benzo [a] pyrene hydroxylase system exists in the nucleus provides a plausible nexus between such toxicities and the metabolism of chemical types like thiocarbamyls and polyhalogenates wherein the ultimate species that is presumably generated is short-lived and too reactive to migrate from the endoplasmic reticulum through the nuclear envelope to the DNA. 

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