Volume 549 Number 7673

Editorials

News

News Features

News & Views

Drain the swamp to beat glioma p.460

Efforts to treat brain tumours by targeting cancer cells have had only modest clinical success. It emerges that targeting a protein secreted from neurons adjacent to the tumour might be a useful alternative approach. See Letter p.533

doi: 10.1038/nature24141

Evaporating planetesimals p.461

Two studies show that evaporation of molten rock was intrinsic to the formation of Earth and other rocky bodies in the Solar System, suggesting that violent collisions played a key part in the formation process. See Letters p.507 & p.511

doi: 10.1038/549461a

Vitamin C regulates stem cells and cancer p.462

It emerges that high levels of vitamin C in blood-forming stem cells influence the number and function of the cells and affect the development of leukaemia, through binding to a tumour-suppressor protein, Tet2. See Article p.476

doi: 10.1038/nature23548

Taking control of spin currents p.464

Conventional wisdom dictates that an electron's magnetic moment and momentum are strongly coupled only in materials made of heavy elements. An experiment demonstrates a striking counterexample. See Letter p.492

doi: 10.1038/549464a

Bad blood promotes tumour progression p.465

Mutations that drive the abnormal expansion of progenitor subpopulations of blood cells are known to cause leukaemia. A genetic analysis reveals that these clonal blood stem-cell mutations are also common in people who have solid tumours.

doi: 10.1038/549465a

Mum's bacteria linked to baby's behaviour p.466

Infection during pregnancy increases the risk of neurodevelopmental disorders, such as autism, in offspring. Mouse studies now reveal a link between gut bacteria and atypical brain-circuit connections. See Article p.482 & Letter p.528

doi: 10.1038/nature24139

Articles

Axonal synapse sorting in medial entorhinal cortex p.469

Path-length-dependent axonal synapse sorting of local presynaptic axons of excitatory neurons in the rat medial entorhinal cortex results in sequential targeting of inhibitory and excitatory neurons, which are connected by a cellular feedforward inhibition circuit.

doi: 10.1038/nature24005

Letters

Early trace of life from 3.95 Ga sedimentary rocks in Labrador, Canada p.516

The authors provide evidence for the existence of life on Earth in the earliest known sedimentary rocks and suggest that the presence of organic carbon, and low stable-isotope values of graphite from sedimentary rocks in Labrador pushes back the existence of organic life to beyond 3.95 billion years.

doi: 10.1038/nature24019

Epigenetic restriction of extraembryonic lineages mirrors the somatic transition to cancer p.543

In mammals, the canonical somatic DNA methylation landscape is established upon specification of the embryo proper and subsequently disrupted within many cancer types. However, the underlying mechanisms that direct this genome-scale transformation remain elusive, with no clear model for its systematic acquisition or potential developmental utility. Here, we analysed global remethylation from the mouse preimplantation embryo into the early epiblast and extraembryonic ectoderm. We show that these two states acquire highly divergent genomic distributions with substantial disruption of bimodal, CpG density-dependent methylation in the placental progenitor. The extraembryonic epigenome includes specific de novo methylation at hundreds of embryonically protected CpG island promoters, particularly those that are associated with key developmental regulators and are orthologously methylated across most human cancer types. Our data suggest that the evolutionary innovation of extraembryonic tissues may have required co-option of DNA methylation-based suppression as an alternative to regulation by Polycomb-group proteins, which coordinate embryonic germ-layer formation in response to extraembryonic cues. Moreover, we establish that this decision is made deterministically, downstream of promiscuously used—and frequently oncogenic—signalling pathways, via a novel combination of epigenetic cofactors. Methylation of developmental gene promoters during tumorigenesis may therefore reflect the misappropriation of an innate trajectory and the spontaneous reacquisition of a latent, developmentally encoded epigenetic landscape.

doi: 10.1038/nature23891