Proteins associated with chromatin in different extracts.
Sperm nuclei were incubated for 20 mins in either metaphase extract, interphase extract, in metaphase extract supplemented with 0.5 or 3 mM 6-DMAP and 0.3mM CaCl2 (“metaphase+6-DMAP”), or in interphase extract supplemented with 7 or 35 nM geminin. Chromatin was isolated and immunoblotted for Orc1, Cdc6, Cdt1, Mcm7 and geminin.