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Vogel, K. J.

Publications and source records attributed to Vogel, K. J..

4 recordsLinked to original sources

Genome Report: Improved chromosome-level genome assembly of the American cockroach, Periplaneta americana

1The American cockroach, Periplaneta americana, is a cosmopolitan insect notorious for thriving among humans undeterred by attempts to eliminate it. The traits that contribute to its ubiquity as an opportunistic pest, such as long lifespan, expansive neurosensory capacity, and nutritional flexibility, also make P. americana an excellent invertebrate model organism with a long history in neuroscience and physiological research. Current genetic resources available for P. americana highlight its large, complex genome and richly diverse transcriptional capabilities, but fall short of producing a complete, chromosome-level genome. Here, we present a high-quality de novo genome assembly of a laboratory-raised adult female P. americana using a combination of high fidelity PacBio long reads and Hi-C sequencing. The final 3.23 Gb genome was assembled with chromosomal resolution into 17 scaffolds, consistent with previous karyotype analysis, and has a scaffold N50 of 188.1 Mb and genome BUSCO score of 99.7%. This assembly includes a chromosome that was missing from the previous reference genome for this species. Protein prediction and annotation were performed via the NCBI Eukaryotic Genome Annotation Pipeline, which identified 16,780 protein-coding genes and generated an annotation BUSCO score of 97.8%. Ortholog comparisons with available Blattodea assemblies highlight the expanded chemosensory and immune capabilities of P. americana compared to termite relatives. This genome assembly is a valuable tool for facilitating future research on the biology and evolution of this remarkable insect.

genomics↗

RNAi-mediated knockdown of two orphan G-protein coupled receptors reduces fecundity in the yellow fever mosquito Aedes aegypti

G-protein coupled receptors (GPCRs) control numerous physiological processes in insects, including reproduction. While many GPCRs have known ligands, orphan GPCRs do not have identified ligands in which they bind. Advances in genomic sequencing and phylogenetics provide the ability to compare orphan receptor protein sequences to sequences of characterized GPCRs, and thus gain a better understanding of their potential function. Our study investigated two orphan GPCRs, AAEL003647 and AAEL019988, in the yellow fever mosquito, Aedes aegypti. From our phylogenetic analysis, we found that AAEL003647 is orthologous to the SIFamide-2/SMYamide receptor, while AAEL019988 is orthologous to the Trapped in endoderm (Tre1) receptor of Drosophila melanogaster. Tissue-specific expression analysis revealed that both receptors had highest expression in the ovaries, suggesting they may be important for reproduction. We then used RNA interference (RNAi) to knock down both genes and found a significant reduction in the number of eggs laid per individual female mosquito, suggesting both receptors are important for Ae. aegypti reproduction.

physiology↗

Microbiomes of blood feeding triatomines in the context of their predatory relatives and the environment

AbstractThe importance of gut microbiomes has become generally recognized in vector biology. This study addresses microbiome signatures in North American Triatoma species of public health significance (vectors of Trypanosoma cruzi) linked to their blood feeding strategy and the natural habitat. To place the Triatoma associated microbiomes within a complex evolutionary and ecological context, we sampled sympatric Triatoma populations, related predatory reduviids, unrelated ticks, and environmental material from vertebrate nests where these arthropods reside. Along with five Triatoma species, we have characterized microbiomes of five reduviids (Stenolemoides arizonensis, Ploiaria hirticornis, Zelus longipes, and two Reduvius species), a single soft tick species, Ornithodoros turicata, and environmental microbiomes from selected sites in Arizona, Texas, Florida and Georgia. The microbiomes of predatory reduviids lack a shared core microbiota. Like in triatomines, microbiome dissimilarities among species corelate with dominance of a single bacterial taxa. These include Rickettsia, Lactobacillus, Candidatus Midichloria, and Zymobacter, which are often accompanied by known symbiotic genera, i.e., Wolbachia, Candidatus Lariskella, Asaia, Gilliamella, and Burkholderia. We have further identified compositional convergence of analyzed microbiomes in respect to the host phylogenetic distance in both blood feeding and predatory reduviids. While microbiomes of two reduviid species from Emesinae family reflect their close relationship, the microbiomes of all Triatoma species repeatedly form a distinct monophyletic cluster highlighting their phylosymbiosis. Furthermore, based on environmental microbiome profiles and blood meal analysis, we propose three epidemiologically relevant and mutually interrelated bacterial sources for Triatoma microbiomes, i.e., host abiotic environment, host skin microbiome, and pathogens circulating in host blood. ImportanceThis study places microbiomes of blood feeding North American Triatoma vectors (Reduviidae) into a broader evolutionary and ecological context provided by related predatory assassin bugs (Reduviidae), another unrelated vector species (soft tick Ornithodor turicata), and the environment these arthropods cohabit. For both vectors, microbiome analyses suggest three interrelated sources of bacteria, i.e., microbiome of vertebrate nests as their natural habitat, vertebrate skin microbiome, and pathobiome circulating in vertebrate blood. Despite an apparent influx of environment-associated bacteria into the arthropod microbiomes, Triatoma microbiomes retain their specificity, forming a distinct cluster that significantly differ from both predatory relatives and ecologically comparable ticks. Similarly, within the related predatory Reduviidae, we found the host phylogenetic distance to underlie microbiome similarities.

ecology↗

Using axenic and gnotobiotic insects to examine the role of different microbes on the development and reproduction of the kissing bug Rhodnius prolixus (Hemiptera: Reduviidae)

Kissing bugs (Hempitera: Reduviidae) are obligately and exclusively blood feeding insects. Vertebrate blood is thought to provide insufficient B vitamins to insects, which rely on obligate symbiotic relationships with bacteria that provision these nutrients. Kissing bugs harbor environmentally acquired bacteria in their gut lumen, without which they are unable to develop to adulthood. Early experiments identified a single bacterial species, Rhodococcus rhodnii, as a symbiont of Rhodnius prolixus, but modern studies of the kissing bug microbiome suggest that R. rhodnii is not always present or abundant in wild-caught individuals. We asked whether R. rhodnii or other bacteria alone could function as symbionts of R. prolixus. Bacteria-free (axenic) insects were produced whose microbiome could be experimentally manipulated to produce insects with known microbiomes (gnotobiotic). We found that gnotobiotic insects harboring R. rhodnii alone developed faster, had higher survival, and laid more eggs than gnotobiotic R. prolixus harboring other bacterial monocultures, including other described symbionts of kissing bugs and several related Rhodococcus species. R. rhodnii grew to high titer in the guts of R. prolixus while other tested species were found at much lower abundance. Rhodococcus species tested had nearly identical B vitamin biosynthesis genes, and dietary supplementation of B vitamins had a relatively minor effect on development and survival of gnotobiotic R. prolixus. Our results indicate that R. prolixus have a higher fitness when harboring R. rhodnii than other bacteria tested, and that symbiont B vitamin synthesis is likely a necessary but not sufficient function of gut bacteria in kissing bugs.

microbiology↗