Biology subjects

Oppert, B.

Publications and source records attributed to Oppert, B..

3 recordsLinked to original sources

bioRxiv2022

Genome and Genetic Engineering of the House Cricket (Acheta domesticus) Applications for Sustainable Agriculture

The house cricket, Acheta domesticus, is one of the most farmed insects worldwide and the foundation of an emerging industry for the use of insects as a sustainable food source. Edible insects present a promising alternative for protein production amid a plethora of recent reports on climate change and biodiversity loss largely driven by agriculture. As with other agricultural crops, genetic resources are needed to improve crickets for food and other applications. We present the first high quality annotated genome assembly of A. domesticus which was assembled from long read data and scaffolded to chromosome level from long range data, providing information on promoters and genes needed for genetic manipulation. Gene groups that may be useful for improving the value of these insects to farmers were manually annotated, mainly genes related to immunity. Metagenome scaffolds in the A. domesticus assembly, including those from bacteria, other microbes and viruses such as Invertebrate Iridescent Virus 6 (IIV6), were submitted in a separate accession as host-associated sequences. We demonstrate both CRISPR/Cas9-mediated knock-in and knock-out of selected genes and discuss implications for the food, pharmaceutical and other industries. RNAi was demonstrated to disrupt the function of the vermilion eye-color gene to produce a useful white-eye biomarker phenotype. We are utilizing these data to develop base technologies and methodologies for downstream commercial applications, including the generation of more nutritious and disease resistant crickets as well as lines producing valuable bioproducts such as vaccines and antibiotics. We also discuss how this foundational research can play a critical role in utilizing the largest, most diverse yet almost entirely untapped biological resource on Earth: Class Insecta. Significance StatementSequencing and assembly of the genome of the house cricket has led to improvements in farmed insects for food, pharmaceutical and other applications.

genomics↗

bioRxiv2018

The genome of the water strider Gerris buenoi reveals expansions of gene repertoires associated with adaptations to life on the water

The semi-aquatic bugs conquered water surfaces worldwide and occupy ponds, streams, lakes, mangroves, and even open oceans. As such, they inspired a range of scientific studies from ecology and evolution to developmental genetics and hydrodynamics of fluid locomotion. However, the lack of a representative water strider genome hinders thorough investigations of the mechanisms underlying the processes of adaptation and diversification in this group. Here we report the sequencing and manual annotation of the Gerris buenoi (G. buenoi) genome, the first water strider genome to be sequenced so far. G. buenoi genome is about 1 000Mb and the sequencing effort recovered 20 949 predicted protein-coding genes. Manual annotation uncovered a number of local (tandem and proximal) gene duplications and expansions of gene families known for their importance in a variety of processes associated with morphological and physiological adaptations to water surface lifestyle. These expansions affect key processes such as growth, vision, desiccation resistance, detoxification, olfaction and epigenetic components. Strikingly, the G. buenoi genome contains three Insulin Receptors, a unique case among metazoans, suggesting key changes in the rewiring and function of the insulin pathway. Other genomic changes include wavelength sensitivity shifts in opsin proteins likely in association with the requirements of vision in water habitats. Our findings suggest that local gene duplications might have had an important role during the evolution of water striders. These findings along with the G. buenoi genome open exciting research opportunities to understand adaptation and genome evolution of this unique hemimetabolous insect.

genomics↗

bioRxiv2017

A model species for agricultural pest genomics: the genome of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome and are rapidly evolving compared to other Coleoptera, and high levels of nucleotide diversity in rapidly growing pest populations. Adaptations to plant feeding are evident in gene expansions and differential expression of digestive enzymes in gut tissues, as well as expansions of gustatory receptors for bitter tasting. Surprisingly, the suite of genes involved in insecticide resistance is similar to other beetles. Finally, duplications in the RNAi pathway might explain why Leptinotarsa decemlineata has high sensitivity to dsRNA. The L. decemlineata genome provides opportunities to investigate a broad range of phenotypes and to develop sustainable methods to control this widely successful pest.

genomics↗