Electron-microscopic observations on Sendai virus-induced chromosome pulverization in HeLa cells

Sendai virus-induced chromosome pulverization in HeLa cells was studied with a method which permits both light and electron microscopy of the cells showing chromosome damage. The ultrastructure of pulverized chromatin showed great resemblance to normal interphase or prophase chromatin and was easily differentiated from metaphase chromatin. The findings of disrupted nuclear membranes in the nuclei showing chromosome pulverization point to the possibility that lysis of the nuclear membrane is one of the initial events in chromosome pulverization.