Project description:Nosema is a diverse fungal genus of microsporidian unicellular, obligate symbionts of insects and other arthropods. We performed a comparative genomic analysis of N. muscidifuracis, a Nosema species infecting parasitoid wasp genus Muscidifurax, with six other genome-sequenced Nosema species. A sequence motif containing at least three consecutive Cs was significantly enriched immediately upstream of the start codon in all seven Nosema genomes. Interestingly, this motif is present in ~90% of highly expressed genes, compared to ~20% in lowly expressed genes N. muscidifuracis, which may function as a cis-regulatory element for gene expression control and regulation. Our study provides new insights into the gene regulation evolution in Nosema.
Project description:The efficiency of host-seeking behavior is crucial to the reproductive performance of female parasitoids. Initially, parasitoids may use chemical information garnered from the microhabitat in which they emerge to locate hosts. Spalangia cameroni and Muscidifurax raptor are commercially available parasitoids of filth flies. Postemergence exposure to a specific manure may provide a way to increase parasitism in specific microhabitats found at livestock facilities upon release. In this study, female parasitoids of both species were exposed to equine manure, bovine manure, or clean pupae. Females from each emergence exposure were tested in a two-choice arena (house fly hosts in bovine manure versus clean pupae, equine manure versus clean pupae, and equine manure versus bovine manure) for progeny production. There was a detectable but small effect of postemergence exposure on S. cameroni, but it was not sufficient to reverse innate preferences. Females consistently produced more progeny in hosts found in any manure over clean pupae, and in equine manure over bovine manure. The effect of postemergence exposure on M. raptor was also detectable but small. Females produced equal numbers of progeny in bovine manure versus clean pupae, as opposed to preferring to oviposit in clean pupae as with all other treatments. Preferences by M. raptor were overall less marked than for S. cameroni; indeed most of the variability observed for this species did not result from the treatment design. Residual host mortality was also detectably altered by exposure in both species, but the effect was small. Thus, postemergence exposure did not consistently and effectively manipulate these parasitoids to producing progeny in different exposure manures, suggesting that microhabitat preferences are largely determined by other factors.
Project description:Five species of Muscidifurax Girault & Sanders (Hymenoptera: Pteromalidae) are studied from mainland China, of which three new species, M.similadanacus Xiao & Zhou, sp. n., M.sinesensilla Xiao & Zhou, sp. n., M.neoraptorellus Xiao & Zhou, sp. n., and one newly recorded species, M.adanacus Doganlar, are reported. All species have been reared from pupae of Muscadomestica Linnaeus. A key to Chinese Muscidifurax and illustrations of external features of the species are provided.