A simple method for isolation of DNA fragments associated with the nuclear lamina in vivo.

We describe a simple method for the purification of DNA fragments associated with the nuclear lamina in vivo. Ehrlich ascite tumor cells are first u.v.-irradiated to crosslink DNA to proteins. The nuclear lamina is then isolated and purified by low-speed centrifugation through a cushion of 40% sucrose. The material sedimenting through the created density barrier represents nuclear lamina of a very high purity, free from any DNA fragments except those which were in a crosslinking distance to it in vivo.