Alteration of a lepidopteran peritrophic membrane by baculoviruses and enhancement of viral infectivity

Location and nucleotide sequence of the gene encoding the viral enhancing factor of the Trichoplusia ni granulosis virus

“…It is not known whether homologues of the VEF protein are present in all baculoviruses, but it is known that AcMNPV possesses a factor which specifically degrades a 68K glycoprotein in the PM of T. ni larvae and enhances baculovirus infections (Derksen & Granados, 1988). Although the identity of this factor is unknown, it does not appear to be related to VEF at either the protein or DNA level (Fig.…”

“…The initial studies with the viral enhancing factor of TnGV have shown that it is a biologically active protein of approximately 101K which can enhance AcMNPV infection in both neonate and fourth instar T. ni larvae (Derksen & Granados, 1988;Gallo et al, 1991). It is apparently resistant to both degradation by midgut alkaline proteases and u.v.…”

“…A viral enhancing factor (VEF) with an Mr of 101K which was localized within the granules of Trichoplusia ni granulosis virus (TnGV) was recently identified (Derksen & Granados, 1988;Granados & Corsaro, 1990). VEF apparently caused the degradation of three high Mr peritrophic membrane (PM) structural glycoproteins; therefore, its predicted mode of action was the temporary structural disruption of the T. ni larval PM.…”

Structural and ultrastructural studies of Anticarsia gemmatalis midgut cells infected with the baculovirus A. gemmatalis nucleopolyhedrovirus

“…The ODV presumably have to penetrate the peritrophic membrane through the pores in order to gain access to the columnar epithelial cells (Barbehenn and Martin, 1995). Previous studies have shown that protein factors found in the occlusion body of baculovirus may be involved in the disruption of the peritrophic membrane (Derksen and Granados, 1988, Greenspan Galo et al, 1991and Bischoff and Slavicek, 1997.…”

Recent advances in the molecular biology of entomopoxviruses

“…Recent evidence indicates that there is a factor associated with the spheroids that can enhance the effectiveness of a nuclear polyhedrosis virus (NPV) against the larval host much like the factor discovered in certain granulosis viruses (Tanada & Hukuhara, 1971;Derksen & Granados, 1988;Xu & Hukuhara, 1992. The spheroids of the armyworm, Pseudaletia separata, were solubilized by alkali and separated on Sephacryl columns followed by hydroxyapatite chromatography.…”