The Pacific oyster Crassostrea gigas belongs to one of the most species-rich but genomically poorly explored phyla, the Mollusca. Here we report the sequencing and assembly of the oyster genome using short reads and a fosmid-pooling strategy, along with transcriptomes of development and stress response and the proteome of the shell. The oyster genome is highly polymorphic and rich in repetitive sequences, with some transposable elements still actively shaping variation. Transcriptome studies reveal an extensive set of genes responding to environmental stress. The expansion of genes coding for heat shock protein 70 and inhibitors of apoptosis is probably central to the oyster's adaptation to sessile life in the highly stressful intertidal zone. Our analyses also show that shell formation in molluscs is more complex than currently understood and involves extensive participation of cells and their exosomes. The oyster genome sequence fills a void in our understanding of the Lophotrochozoa.Oceans cover approximately 71% of the Earth's surface and harbour most of the phylum diversity of the animal kingdom. Understanding marine biodiversity and its evolution remains a major challenge. The Pacific oyster C. gigas (Thunberg, 1793) is a marine bivalve belonging to the phylum Mollusca, which contains the largest number of described marine animal species 1 . Molluscs have vital roles in the functioning of marine, freshwater and terrestrial ecosystems, and have had major effects on humans, primarily as food sources but also as sources of dyes, decorative pearls and shells, vectors of parasites, and biofouling or destructive agents. Many molluscs are important fishery and aquaculture species, as well as models for studying neurobiology, biomineralization, ocean acidification and adaptation to coastal environments under climate change 2,3 . As the most speciose member of the Lophotrochozoa, phylum Mollusca is central to our understanding of the biology and evolution of this superphylum of protostomes.As sessile marine animals living in estuarine and intertidal regions, oysters must cope with harsh and dynamically changing environments. Abiotic factors such as temperature and salinity fluctuate wildly, and toxic metals and desiccation also pose serious challenges. Filter-feeding oysters face tremendous exposure to microbial pathogens. Oysters do have a notable physical line of defence against predation and desiccation in the formation of thick calcified shells, a key evolutionary innovation making molluscs a successful group. However, acidification of the world's oceans by uptake of anthropogenic carbon dioxide poses a potentially serious threat to this ancient adaptation 4 . Understanding biomineralization and molluscan shell formation is, thus, a major area of interest 5 . Crassostrea gigas is also an interesting model for developmental biology owing to its mosaic development with typical molluscan stages, including trochophore and veliger larvae and metamorphosis.A complete genome sequence of C. gigas would enable a more th...

Bats are the only mammals capable of sustained flight and are notorious reservoir hosts for some of the world's most highly pathogenic viruses, including Nipah, Hendra, Ebola, and severe acute respiratory syndrome (SARS). To identify genetic changes associated with the development of bat-specific traits, we performed whole-genome sequencing and comparative analyses of two distantly related species, fruit bat Pteropus alecto and insectivorous bat Myotis davidii. We discovered an unexpected concentration of positively selected genes in the DNA damage checkpoint and nuclear factor κB pathways that may be related to the origin of flight, as well as expansion and contraction of important gene families. Comparison of bat genomes with other mammalian species has provided new insights into bat biology and evolution.

The naked mole rat (NMR, Heterocephalus glaber) is a strictly subterranean, extraordinarily long-lived eusocial mammal1. Although the size of a mouse, its maximum lifespan exceeds 30 years and makes this animal the longest living rodent. NMRs show negligible senescence, no age-related increase in mortality, and high fecundity until death2. In addition to delayed aging, NMRs are resistant to both spontaneous cancer and experimentally induced tumorigenesis3,4. NMRs pose a challenge to the theories that link aging, cancer and redox homeostasis. Although characterized by significant oxidative stress5, the NMR proteome does not show age-related susceptibility to oxidative damage nor increased ubiquitination6. NMRs naturally reside in large colonies with a single breeding female, the “queen,” who suppresses the sexual maturity of her subordinates11. NMRs also live in full darkness, at low oxygen and high carbon dioxide concentrations7, and are unable to sustain thermogenesis8 nor feel certain types of pain9,10. Here we report sequencing and analysis of the NMR genome, which revealed unique genome features and molecular adaptations consistent with cancer resistance, poikilothermy, hairlessness, altered visual function, circadian rhythms and taste sensing, and insensitivity to low oxygen. This information provides insights into NMR’s exceptional longevity and capabilities to live in hostile conditions, in the dark and at low oxygen. The extreme traits of NMR, together with the reported genome and transcriptome information, offer unprecedented opportunities for understanding aging and advancing many other areas of biological and biomedical research.

Locusts are one of the world’s most destructive agricultural pests and represent a useful model system in entomology. Here we present a draft 6.5 Gb genome sequence of Locusta migratoria, which is the largest animal genome sequenced so far. Our findings indicate that the large genome size of L. migratoria is likely to be because of transposable element proliferation combined with slow rates of loss for these elements. Methylome and transcriptome analyses reveal complex regulatory mechanisms involved in microtubule dynamic-mediated synapse plasticity during phase change. We find significant expansion of gene families associated with energy consumption and detoxification, consistent with long-distance flight capacity and phytophagy. We report hundreds of potential insecticide target genes, including cys-loop ligand-gated ion channels, G-protein-coupled receptors and lethal genes. The L. migratoria genome sequence offers new insights into the biology and sustainable management of this pest species, and will promote its wide use as a model system.

Exosomes are attractive nucleic-acid carriers because of their favourable pharmacokinetic and immunological properties and of their ability to penetrate physiological barriers that are impermissible to synthetic drug-delivery vehicles. However, inserting exogenous nucleic acids, especially large messenger RNAs (mRNAs), into cell-secreted exosomes leads to low yields. Here, we report a cellular-nanoporation method for the production of large quantities of exosomes containing therapeutic mRNAs and targeting peptides. We transfected various source cells with plasmid DNAs, and stimulated the cells with a focal and transient electrical stimulus that promotes the release of exosomes carrying transcribed mRNAs and targeting peptides. Compared to bulk electroporation and to other exosome-production strategies, cellular nanoporation produced up to 50-fold more exosomes and more than a 10 3 -fold increase in exosomal mRNA transcripts, even from cells with low basal levels of exosome secretion. In orthotopic PTEN-deficient glioma mouse models, mRNA-containing exosomes restored tumour-suppressor function, enhanced tumourgrowth inhibition, and increased animal survival. Cellular nanoporation may enable the use of exosomes as a universal nucleic-acid carrier for applications requiring transcriptional manipulation.