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The Bemisia tabaci cryptic species complex harbors a diversified flora of primary and secondary endosymbionts, which plays crucial roles in many aspects of the insect biology. The endosymbiont infection pattern is dependent upon many factors, including host plant and geographic origin. In Brazil, the invasion of B. tabaci Middle East-Asia Minor-1 (MEAM 1) populations was observed in tomato (Solanum lycopersicum L.) fields in the 1990s, which was followed by severe begomovirus epidemics. Here we confirmed the vertical transmission of "Candidatus Portiera" and the localization of secondary endosymbionts in distinct B. tabaci developmental stages. Hamiltonella defensa was detected in bacteriocytes but also scattered in the leg muscles as well as in the male heads. Wolbachia-specific signals were found in eggs, nymphs, male adults, and female gonads in predominant association with bacteriocytes. These results were somewhat surprising since Wolbachia infection is rarely found in MEAM 1 populations from the Old World. Our results reinforce the notion that endosymbiont infection pattern may vary according to the insect population, gender, developmental stage, and geographic origin. This characterization will provide tools to study the endosymbiont function in the transmission ability/efficiency of a complex of tomato-infecting bipartite begomoviruses by B. tabaci under Neotropical conditions.

Lonomia obliqua (Lepidoptera: Saturniidae) is a species of medical importance due to the severity of reactions caused by accidental contact with the caterpillar bristles. Several natural pathogens have been identified in L. obliqua, and among them the baculovirus Lonomia obliqua multiple nucleopolyhedrovirus (LoobMNPV). The complete genome of LoobMNPV was sequenced and shown to have 120,022 bp long with 134 putative open reading frames (ORFs). Phylogenetic analysis of the LoobMNPV genome showed that it belongs to Alphabaculovirus group I (lepidopteran-infective NPV). A total of 12 unique ORFs were identified with no homologs in other sequenced baculovirus genomes. One of these, the predicted protein encoded by loob035, showed significant identity to an eukaryotic transcription terminator factor (TTF2) from the Lepidoptera Danaus plexippus, suggesting an independent acquisition through horizontal gene transfer. Homologs of cathepsin and chitinase genes, which are involved in host integument liquefaction and viral spread, were not found in this genome. As L. obliqua presents a gregarious behavior during the larvae stage the impact of this deletion might be neglectable.

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Bovine alphaherpesvirus type 5 (BoHV-5) is one of the main agents responsible for meningoencephalitis in cattle in Brazil, causing significant economic losses. It is known that other viruses of the Herpesviridae family such as Bovine alphaherpesvirus type 1, Swine alphaherpesvirus type 1, and the Human alphaherpesvirus types 1 and 2 encode genes homologous to BoHV-5, with recognized action in the control of apoptosis. The objective of this work was to express the BoHV-5 US3 gene in a baculovirus-based expression system for the production of the serine/threonine kinase protein and to evaluate its activity in the control of apoptosis in vitro. A recombinant baculovirus derived from the Autographa californica multiple nucleopolyhedrovirus (AcMNPV) containing the US3 gene and a deletion in the baculovirus anti-apoptotic p35 gene was constructed using the Bac-to-Bac™ system. This recombinant baculovirus was used to evaluate the anti-apoptotic activity of the recombinant US3 protein in insect cells comparing with two other AcMNPV recombinants, one containing a functional copy of the AcMNPVanti-apoptotic p35 gene and an AcMNPV p35 knockout virus with the anti-apoptotic iap-3 gene from Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV). We found that the caspase level was higher in insect cells infected with the US3-contanining recombinant virus than in cells infected with the AcMNPV recombinants containing the p35 and iap-3 genes. These results indicate that the BoHV-5 US3 protein kinase gene is not able to block apoptosis in insect cells induced by the infection of a p35 knockout AcMNPV.