FIG. 1.

Purity and integrity of isolated nuclei. Nuclei isolated from HSV-1 17⁺-infected HeLa cells were mounted in Epon and analyzed by electron microscopy. Panel A indicates the relative purity of the preparation at low magnification (×960), while panels B and C show that the isolation procedure preserved the integrity of both nuclear envelopes at higher magnification (×12,400 and ×31,200, respectively). Note the presence of multiple capsids both in the nuclei matrix and in the perinuclear space. Bars represent (A) 10 μm, (B) 1 μm, and (C) 200 nm.