As it is known that food waste can be reduced by the larvae of Hermetia illucens (Black soldier fly, BSF), the scientific and commercial value of BSF larvae has increased recently. We hypothesised that the ability of catabolic degradation by BSF larvae might be due to intestinal microorganisms. Herein, we analysed the bacterial communities in the gut of BSF larvae by pyrosequencing of extracting intestinal metagenomic DNA from larvae that had been fed three different diets. The 16S rRNA sequencing results produced 9737, 9723 and 5985 PCR products from larval samples fed food waste, cooked rice and calf forage, respectively. A BLAST search using the EzTaxon program showed that the bacterial community in the gut of larvae fed three different diets was mainly composed of the four phyla with dissimilar proportions. Although the composition of the bacterial communities depended on the different nutrient sources, the identified bacterial strains in the gut of BSF larvae represented unique bacterial species that were unlike the intestinal microflora of other insects. Thus, our study analysed the structure of the bacterial communities in the gut of BSF larvae after three different feedings and assessed the application of particular bacteria for the efficient degradation of organic compounds.

Two endosymbionts, an obligate primary symbiont and a facultative secondary symbiont, are harbored within the invasive red gum (eucalyptus) lerp psyllid, Glycaspis brimblecombei, in California. An extensive survey of diversity and frequency of G. brimblecombei's secondary symbiont in multiple populations throughout the state of California was conducted using PCR detection, restriction enzymes, cloning, and sequencing. A total of 380 G. brimblecombei individuals in 19 populations were screened for secondary symbionts. Based on molecular screening results, only one type of secondary symbiont was present in G. brimblecombei populations in California. Overall, 40% of the 380 psyllids screened were infected with the secondary symbiont. Interestingly, secondary symbiont infection frequencies in G. brimblecombei populations varied dramatically from 0 to 75% and were significantly related to parasitism pressure by Psyllaphaegus bliteus, a solitary endoparasitoid of the psyllid.Insect bacterial endosymbionts are harbored in a wide diversity of insects (2,7,14,32). Despite the prevalence of endosymbionts throughout many insect orders, little is known about the role and maintenance of endosymbionts within insect hosts. In general, an endosymbiont-host association can be obligate for survival and/or reproduction of the host (termed a primary symbiont here) or facultative and therefore not necessary for host survival and/or reproduction (termed a secondary symbiont [SS] here) (7, 26). The role of primary symbionts to their host is thought to be nutritional enrichment (4,5,14,15,19,20,27). Alternatively, the roles of facultative SSs are not well understood (2, 3). Nevertheless, SSs have recently been found to exert a variety of effects on the phenotype of Acyrthosiphon pisum Harris (Hemiptera: Aphidae) (8,17,18,25,29,35).Little is known about the roles SSs play within their insect hosts other than A. pisum. Although SSs are known to occur in 33 psyllid species (26,30,34), no information has yet been published on the frequency of SSs within and among psyllid populations or their effect on psyllid phenotypes. It is important to understand insect-endosymbiont interactions because endosymbionts may play major evolutionary roles in eukaryotes by influencing interspecific interactions, distributions, and fitness during ecological time scales in populations.In the state of California, the invasive red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psylloidea), its preferred and prevalent host plant Eucalyptus camaldulensis Dehnhardt (Myrtales: Myrtaceae) (6), and its parasitoid Psyllaphaegus bliteus Riek (Hymenoptera: Encyrtidae) provide an ideal system for the study of endosymbiont-host interactions on a geographic scale. Eucalyptus spp. were introduced from Australia to California as seeds around 1850 (13); E. camaldulensis is the most abundant host plant species of G. brimblecombei and has been planted throughout the state (13). In 1998, G. brimblecombei invaded California from Australia (24) and quickly became estab...

No abstract

DJ-1, a Parkinson's disease (PD)–associated gene, has been shown to protect against oxidative stress in Drosophila. However, the molecular mechanism underlying oxidative stress-induced phenotypes, including apoptosis, locomotive defects, and lethality, in DJ-1-deficient flies is not fully understood. Here we showed that Daxx-like protein (DLP), a Drosophila homologue of the mammalian Death domain-associated protein (Daxx), was upregulated under oxidative stress conditions in the loss-of-function mutants of Drosophila DJ-1β, a Drosophila homologue of DJ-1. DLP overexpression induced apoptosis via the c-Jun N-terminal kinase (JNK)/Drosophila forkhead box subgroup O (dFOXO) pathway, whereas loss of DLP increased resistance to oxidative stress and UV irradiation. Moreover, the oxidative stress-induced phenotypes of DJ-1β mutants were dramatically rescued by DLP deficiency, suggesting that enhanced expression of DLP contributes to the DJ-1β mutant phenotypes. Interestingly, we found that dFOXO was required for the increase in DLP expression in DJ-1β mutants and that dFOXO activity was increased in the heads of DJ-1β mutants. In addition, subcellular localization of DLP appeared to be influenced by DJ-1 expression so that cytosolic DLP was increased in DJ-1β mutants. Similarly, in mammalian cells, Daxx translocation from the nucleus to the cytosol was suppressed by overexpressed DJ-1β under oxidative stress conditions; and, furthermore, targeted expression of DJ-1β to mitochondria efficiently inhibited the Daxx translocation. Taken together, our findings demonstrate that DJ-1β protects flies against oxidative stress- and UV-induced apoptosis by regulating the subcellular localization and gene expression of DLP, thus implying that Daxx-induced apoptosis is involved in the pathogenesis of DJ-1-associated PD.