The interaction of carcinogenic hydrocarbons with tissues. VII. Fractionation of mouse skin proteins.

Summary Studies have been carried out on the nature of the proteins of mouse skin to which hydrocarbons are bound after topical application. No relation was found between the carcinogenic activities of various hydrocarbons and their inhibition of the incorporation of dl-lysine-2-C 14 into mouse skin proteins. Salt fractionation of the proteins to which 1,2,5,6-dibenzanthracene-9,10-C 14 is bound revealed similar specific activities in all fractions, with that of keratin being the highest. Fractionation of the soluble proteins of mouse skin by vertical column zone electrophoresis is described in detail. A comparison of column electropherograms of the soluble proteins from the skins of mice given the carcinogenic 1,2,5,6-dibenzanthracene-9,10-C 14 and the noncarcinogenic 1,2,3,4-dibenzanthracene-9,10-C 14 demonstrated that in two regions the specific activity was considerably higher in the case of the carcinogenic hydrocarbon, suggesting a specificity of action. One of these zones, in the region of tubes 32 to 42, was incompletely resolved into two peaks. The other zone at the beginning of the electropherogram represents migration toward the cathode at pH 6.8, and the “h” proteins from rat liver to which the hepatocarcinogenic aminoazo dyes are bound exhibit a similar electrophoretic behavior. The relationship between this finding and the process of carcinogenesis is discussed.