The ugly truth is that the plastic microbeads found in many skin scrubs and other personal-care products are a serious pollutant of the marine environment. They should be phased out rapidly.
The replacement of mitochondria does not signal ethical problems.
Reanalysis of the controversy provides a strong example of the self-correcting nature of science.
Educational void risks hampering reconstruction in Middle East.
Sustainable development goals aim to wipe out poverty without wrecking the environment.
Treatment of developing brains offers greater scope for improvement but also intensifies risks.
Prime Minister Stephen Harper's government has cut funding and limited researchers' influence over policy.
Observatory will extend the capabilities of existing US and European facilities, and boost Indian research.
Pair will focus on resolving financial issues after controversial failed merger.
The data contained in tax returns, health and welfare records could be a gold mine for scientists — but only if they can protect people's identities.
The powerhouses of the cell may have more roles than expected. Could that generate problems for mitochondrial replacement therapies?
News & Views
An ultra-high-resolution structure of the core segment of assembled α-synuclein — the protein that aggregates in the brains of patients with Parkinson's disease — has been determined. A neurobiologist and a structural biologist discuss the implications of this advance. See Article p.486
Ships and ocean-observing robots have been used to quantify the amount of nutrients that a storm brings up from the Stygian ocean depths to the sunlit surface — a first step in assessing how storms affect oceanic biomass production.
Human heart tissue has minimal ability to regenerate following injury. But the protein Fstl1, which is normally expressed in the heart's epicardial region, has now been shown to induce regeneration following heart attack. See Article p.479
Neutrons do not normally have orbital angular momentum. But the demonstration that a beam of neutrons can acquire this property, 23 years after it was shown in photons, offers the promise of improved imaging technologies. See Letter p.504
Chromosomal shuffling in parental eggs or sperm can create new characteristics in the next generation. In fruit flies, it seems that mothers with a parasitic infection produce more such recombinant offspring than uninfected mothers.
The enigma of how the most luminous galaxies arise is closer to being solved. New simulations show that these are long-lived massive galaxies powered by prodigious gas infall and the recycling of supernova-driven outflows. See Letter p.496
Despite their clonal origin, some oil palm trees develop fruits that give almost no oil. It emerges that the number of methyl groups attached to a DNA region called Karma determine which plants are defective. See Letter p.533
In response to the need for a defined set of criteria to assess stem-cell potency, this review proposes guidelines for the evaluation of newly derived pluripotent stem cells, from functional assays to integrative molecular analyses of transcriptional, epigenetic and metabolic states.
The secreted factor follistatin-like 1 (FSTL1) becomes undetectable in the epicardium of infarcted hearts; when reconstituted using a collagen patch sutured onto an infarcted heart, FSTL1 can induce cell cycle entry and division of pre-existing cardiomyocytes, thus boosting heart function and survival in mouse and pig models of myocardial infarction.
A short segment of α-synuclein called NACore (residues 68–78) is responsible for the formation of amyloid aggregates responsible for cytotoxicity in Parkinson disease; here the nanocrystal structure of this invisible-to-optical-microscopy segment is determined using micro-electron diffraction, offering insight into its function and simultaneously demonstrating the first use of micro-electron diffraction to solve a previously unknown protein structure.
The cryo-electron microscopy structure of the eukaryotic initiation factor 3 (eIF3) within the larger 43S complex is determined; the improved resolution enables visualization of the secondary structures of the subunits, as well as the contacts between eIF3 and both eIF2 and DHX29.
Submillimetre-bright galaxies at high redshift are the most luminous, heavily star-forming galaxies in the Universe, but cosmological simulations of such galaxies have so far been unsuccessful; now a cosmological hydrodynamic galaxy formation simulation is reported that can form a submillimetre galaxy that simultaneously satisfies the broad range of observed physical constraints.
Observations of water ice on the surface of comet 67P/Churyumov–Gerasimenko show the ice appearing and disappearing in a cyclic pattern that follows local illumination conditions, providing a source of localized activity and leading to cycling modification of the ice abundance on the surface.
Interferometry reveals quantized changes in the angular momentum of neutrons that have been ‘twisted’ by passage through a spiral staircase structure.
The complex anti-HIV alkaloid (+)-batzelladine B is efficiently synthesized by using aromatic heterocycles as synthetic precursors.
A 2,000-kilometre-long volcanic hotspot track is identified in eastern Australia, along which magma composition and volcanic outcrop show a strong correlation with lithospheric thickness, providing an observational constraint on the sub-continental melting depth of mantle plumes.
Species’ range dynamics depend not only on their ability to track climate, but also on the migration of their competitors, and the extent to which novel and current competitors exert differing competitive effects.
Sexual dimorphism in neuronal circuits is proposed to underlie sex differences in behaviour, such as virgin female mice acting maternally toward alien pups, while males ignore or attack them; here the authors show that specific tyrosine hydroxylase-expressing neurons in the hypothalamus are more numerous in mothers than in virgin females and males, and that they control parental behaviour in a sex-specific manner.
This study shows that a vertebrate-specific ubiquitin ligase modulates neural crest specification in Xenopus development and human embryonic stem-cell differentiation; a proteomics approach reveals that the CUL3KBTBD8 ligase modulates translation by targeting the modulators of ribosomes production NOLC1 and its paralogue TCOF1, which is mutated in a neural-crest-associated syndrome.
Neutrophil ageing, which encourages inflammation and vaso-occlusion in a mouse model of sickle-cell disease, is shown to depend on the intestinal microbiota and activation of the TLR/Myd88 signalling pathways.
Somaclonal variation arises in plants and animals when differentiated somatic cells are induced into a pluripotent state, but the resulting clones differ from each other and from their parents. In agriculture, somaclonal variation has hindered the micropropagation of elite hybrids and genetically modified crops, but the mechanism responsible remains unknown. The oil palm fruit ‘mantled’ abnormality is a somaclonal variant arising from tissue culture that drastically reduces yield, and has largely halted efforts to clone elite hybrids for oil production. Widely regarded as an epigenetic phenomenon, ‘mantling’ has defied explanation, but here we identify the MANTLED locus using epigenome-wide association studies of the African oil palm Elaeis guineensis. DNA hypomethylation of a LINE retrotransposon related to rice Karma, in the intron of the homeotic gene DEFICIENS, is common to all mantled clones and is associated with alternative splicing and premature termination. Dense methylation near the Karma splice site (termed the Good Karma epiallele) predicts normal fruit set, whereas hypomethylation (the Bad Karma epiallele) predicts homeotic transformation, parthenocarpy and marked loss of yield. Loss of Karma methylation and of small RNA in tissue culture contributes to the origin of mantled, while restoration in spontaneous revertants accounts for non-Mendelian inheritance. The ability to predict and cull mantling at the plantlet stage will facilitate the introduction of higher performing clones and optimize environmentally sensitive land resources.
BET inhibitors that target bromodomain chromatin readers such as BRD4 are being explored as potential therapeutics in cancer; here, in a MLL–AF9 mouse leukaemia model, resistance to BET inhibitors is shown to emerge from leukaemia stem cells, and be partly due to increased Wnt/β-catenin signalling.
BET bromodomain inhibitors are being explored as potential therapeutics in cancer; here, AML cells are shown to evade sensitivity to BET inhibition through rewiring the transcriptional regulation of BRD4 target genes such as MYC in a process that is facilitated by suppression of PRC2 and WNT signalling activation.
Microorganisms can export toxic fluoride ions through highly selective channels of the Fluc family; here, the crystal structures of two bacterial Fluc homologues are presented, revealing that selectivity for small F− ions may arise from the proteins’ narrow pores and unusual anion coordination.