Early DNA Synthesis in the X-chromosome of Pellia neesiana

Abstract

In the present investigation DNA synthesis of X-chromosome of Pellia neesiana (n=9), Hepaticae, was studied by the use of the H³-thymidine autoradiography.
1. DNA in the heterochromatin of X-chromosome of female Pellia neesiana was found to replicate during the early and the middle stages of DNA synthetic phase.
2. DNA in the euchromatin of both X-chromosome and autosomes was found to replicate continuously from the early to the last stages of DNA synthetic phase.
3. DNA in the heterochromatin of X-chromosome was found to replicate mainly in the diffused state of heterochromatin during the early stage of DNA synthetic phase.