[Autoradiography of lysed L cells with labelled 3H-lysine]

Using the method of fibr-DNA autoradiography, 3H-lysine labeled L cells were examined. Fibr-labeled structures as long as 400 mkm were revealed. The pattern of labeling along fibres was same as when cells were labeled with 3H-thymidine. In cross experiments when 3H-lysine and 3H-thymidine were used simultaneously, the pattern of labeling remained the same. The data obtained may evidence that the complexation of new synthesized histones with DNA takes place synchronously with the replication, and in the points of chromosome replication.