Role of Intranuclear Sacs, Intrasaccate Tubes, and Cytoplasmic Dense Bodies in the Structural Completion of Cytomegalovirus

Abstract

The addition of tegument or matrix proteins and the outermost membrane to human cytomegalovirus (strain AD 169) replicating in human cells appeared to occur differently in the nucleus than in the cytoplasm. In the nucleus cytomegalovirus was completed structurally within intranuclear sacs, as envelopment at the end of tubular structures, containing an electron-dense material, included tegument and outer membrane simultaneously. In the cytoplasm structural completion occurred in separate steps. Tegument could be added by association with dense bodies; then, interaction with the membranes of vacuoles or vesicles provided the outermost covering. Tubes originating in intranuclear sacs have been described previously only in guinea pig cells infected with guinea pig cytomegalovirus.

Herpesviruses associated with mortalities among hatchery-reared larval Pacific oysters Crassostrea gigas

“…The porary envelopment and de-envelopment as nucleo-ovoid ring of nuclear granular material (Fig. 4) is simicapsids pass through the nuclear membrane (Severi lar to that reported in human cytomegalovirus infecet al 1979), and their association with dense bodies tion (Tumilowicz & Powell 1990). If cessation of feed-ing by Crassostrea gigas larvae at 3 to 4 d indicates onset of infection, and most deaths occur at 9 to 10 d , replication may occur over ca 6 d , as in CMV (Smith & de Harven 1973, Roizman et al 1981, although several replication cycles may occur over this period.…”

“…18. Inter-digitating portion of cell showing nucleocapsids containing granular pleomorphic cores; X 110 400 tubular elements (Tumilowicz & Powell 1990), the tem-and Golgi in the cytoplasm (Severi et al 1988). The porary envelopment and de-envelopment as nucleo-ovoid ring of nuclear granular material (Fig.…”