| | Systems biology: Network evolution hinges on history
The effects of mutations in proteins can depend on the occurrence of previous mutations. It emerges that such historical contingency is also important during the evolution of gene regulatory networks.
| Symbiosis: Receptive to infection
EPR3, a plant protein, is found to act as a probable receptor for exopolysaccharide molecules that surround the plant's symbiotic bacteria. The advance sheds light on how recognition is governed in symbiotic relationships.
| Timing and climate forcing of volcanic eruptions for the past 2,500 years
Ice-core and tree-ring data show that large volcanic eruptions in the tropics and high latitudes were primary drivers of temperature variability in the Northern Hemisphere during the past 2,500 years, firmly implicating such eruptions as catalysts in major sixth-century pandemics, famines, and socioeconomic disruptions.
| Progesterone receptor modulates ERα action in breast cancer
Progesterones, oestrogens and their receptors (PR, ERα and ERβ) are essential in normal breast development and homeostasis, as well as in breast cancer; here it is shown that PR controls ERα function by redirecting where ERα binds to the chromatin, acting as a proliferative brake in ERα+ breast tumours.
| Receptor-mediated exopolysaccharide perception controls bacterial infection
This paper describes the discovery of the exopolysaccharide receptor (Epr3) in plants, and shows that its expression is induced upon perception of the bacterial Nod factors; the EPR3 receptor recognizes exopolysaccharides on the surface of rhizobia, thus controlling the symbiotic infection of the roots of legumes.
| Parent stem cells can serve as niches for their daughter cells
Little is known about how the relative proportions of stem cells and differentiated cells are regulated; basal stem/progenitor cells of the mouse airway epithelium self renew and differentiate into secretory and ciliated cells, and basal stem cells continuously send daughter cells a forward niche signal necessary for daughter cell fate maintenance.
| Small-scale filament eruptions as the driver of X-ray jets in solar coronal holes
A study of the formation of X-ray jets in solar coronal holes suggests that this process does not follow the popular 'emerging-flux' model, but instead results from a minifilament eruption akin to the larger-scale filament eruptions that drive larger solar flares and mass ejections.
| The CREB coactivator CRTC2 controls hepatic lipid metabolism by regulating SREBP1
Studies in mice reveal that CREB regulated transcription coactivator 2 (CRTC2) acts as a mediator of mTOR signalling in the liver to regulate SREBP1-controlled lipid homeostasis during feeding and diabetes; overexpression of a CRTC2 mutant defective for mTOR regulation improves the lipogenic program and insulin sensitivity in obese mice.
| Live imaging RNAi screen reveals genes essential for meiosis in mammalian oocytes
A high-content phenotypic screening method has been developed allowing the first systematic RNA interference screen for nearly 800 genes mediating mammalian meiosis.
| Intersecting transcription networks constrain gene regulatory evolution
Epistatic interactions, whereby a mutation's effect is contingent on another mutation, have been shown to constrain evolution within single proteins, and how such interactions arise in gene regulatory networks has remained unclear; here the appearance of pheromone-response regulator binding sites in the regulatory DNA of the a-specific genes of Saccharomyces cerevisiae are shown to have required specific changes in a second pathway during the evolution from its common ancestor with Candida albicans.
| Corrigendum: A diverse range of gene products are effectors of the type I interferon antiviral response
| Corrigendum: Pan-viral specificity of IFN-induced genes reveals new roles for cGAS in innate immunity
| Corrigendum: Passenger deletions generate therapeutic vulnerabilities in cancer
| Universal allosteric mechanism for Gα activation by GPCRs
There are ∼800 human GPCRs and 16 different Gα proteins; this study revealed the molecular details of Gα activation by GPCRs and suggests that a universal activation mechanism governs Gα activation—the details of this mechanism can explain how the GPCR–Gα system diversified rapidly, while conserving the allosteric activation mechanism.
| | Feedback in low-mass galaxies in the early Universe
Feedback in the form of galactic-scale outflows of gas from star-forming, low-mass galaxies allowed ionizing radiation to escape from galaxies when the Universe was about 500 million years old, changing the hydrogen between galaxies from neutral to ionized.
Dawn K. Erb | | Glypican-1 identifies cancer exosomes and detects early pancreatic cancer
Glypican-1 identifies cancer exosomes and serves as a biomarker for detection of early pancreatic cancer in patients and mouse models of the disease; the findings may enable early and non-invasive identification, and prevention of malignant cancer.
Sonia A. Melo, Linda B. Luecke, Christoph Kahlert et al. | Lenalidomide induces ubiquitination and degradation of CK1α in del(5q) MDS
Lenalidomide, a derivative of thalidomide, is an effective drug for myelodysplastic syndrome; lenalidomide binds the CRL4CRBN E3 ubiquitin ligase and promotes degradation of casein kinase 1a, on which the malignant cells rely for survival.
Jan Krönke, Emma C. Fink, Paul W. Hollenbach et al. | | Long-range energy transport in single supramolecular nanofibres at room temperature
Coherent energy transport is key to the operation of the photosynthetic machinery and the successful implementation of molecular electronics; self-assembled supramolecular nanofibres based on carbonyl-bridged triarylamines are now shown to transport singlet excitons over micrometre-scale distances at room temperature.
Andreas T. Haedler, Klaus Kreger, Abey Issac et al. | Cyclic di-GMP acts as a cell cycle oscillator to drive chromosome replication
In Caulobacter crescentus, oscillating levels of the second messenger cyclic-di-GMP drive the cell cycle through regulation of the essential cell cycle kinase CckA; as its levels increase during the G1–S transition, cyclic-di-GMP binds to CckA to inhibit kinase and stimulate phosphatase activity, thereby enabling replication initiation.
C. Lori, S. Ozaki, S. Steiner et al. | Hypoxia fate mapping identifies cycling cardiomyocytes in the adult heart
Fate-mapping hypoxic cells in the mouse heart identifies a rare population of cycling cardiomyocytes, which show characteristics of neonatal cardiomyocytes, including smaller size and mononucleation, and contribute to new cardiomyocyte formation in the adult heart.
Wataru Kimura, Feng Xiao, Diana C. Canseco et al. | Melanoma-intrinsic β-catenin signalling prevents anti-tumour immunity
Only a subset of patients with melanoma responds to new immunotherapeutic therapies; here, β-catenin signalling is identified as an important pathway that confers resistance to this type of approach, with implications for future treatment strategies.
Stefani Spranger, Riyue Bao, Thomas F. Gajewski | Eye-like ocelloids are built from different endosymbiotically acquired components
Dinoflagellate eye-like ocelloids are built from pre-existing organelles of disparate origin, including a cornea-like layer made of mitochondria and a retinal body made of anastomosing plastids.
Gregory S. Gavelis, Shiho Hayakawa, Richard A. White III et al. | Global-scale coherence modulation of radiation-belt electron loss from plasmaspheric hiss
Simultaneous measurements of structured radiation-belt electron losses (in the form of bremsstrahlung X-rays) and plasmaspheric hiss (which causes the losses) reveal that the loss dynamics is coherent with the hiss dynamics on spatial scales comparable to the size of the plasmasphere.
A. W. Breneman, A. Halford, R. Millan et al. | A very luminous magnetar-powered supernova associated with an ultra-long γ-ray burst
A new class of ultra-long-duration γ-ray bursts (GRBs) has recently been suggested, with durations in excess of 10,000 seconds, and now a supernova (SN 2011kl) has been found to be associated with the ultra-long-duration GRB 111209A, allowing a physical understanding of the nature of ultra-long-duration GRBs.
Jochen Greiner, Paolo A. Mazzali, D. Alexander Kann et al. | Unusual biology across a group comprising more than 15% of domain Bacteria
More than 15% of the bacterial domain consists of a radiation of phyla about which very little is known; here, metagenomics is used to reconstruct 8 complete and 789 draft genomes from more than 35 of these phyla, revealing a shared evolutionary history, metabolic limitations, and unusual ribosome compositions.
Christopher T. Brown, Laura A. Hug, Brian C. Thomas et al. | Basin-scale transport of hydrothermal dissolved metals across the South Pacific Ocean
Hydrothermal dissolved iron, manganese, and aluminium from the southern East Pacific Rise is transported several thousand kilometres westward across the South Pacific Ocean; global hydrothermal dissolved iron input is estimated to be more than four times what was previously thought and modelling suggests it must be physically or chemically stabilized in solution.
Joseph A. Resing, Peter N. Sedwick, Christopher R. German et al. | Th17 cells transdifferentiate into regulatory T cells during resolution of inflammation
Analysis of a mouse model shows that during the course of an immune response, helper T cells undergo functional reprogramming to transdifferentiate into regulatory T cells; this T cell plasticity could possibly be exploited to develop better therapies for restoring immune tolerance in autoimmune diseases.
Nicola Gagliani, Maria Carolina Amezcua Vesely, Andrea Iseppon et al. | Global circulation patterns of seasonal influenza viruses vary with antigenic drift
The analysis of more than 9,000 haemagglutinin sequences of human seasonal influenza viruses over a 12-year time period shows that the global circulation patterns of A/H1N1 and B viruses are different from those of the well characterised A/H3N2 viruses; in particular the A/H1N1 and B viruses are shown to persist locally across several seasons and do not display the same degree of global movement as the H3N2 viruses.
Trevor Bedford, Steven Riley, Ian G. Barr et al. | Human body epigenome maps reveal noncanonical DNA methylation variation OPEN
As part of the Epigenome Roadmap Project, genome-wide maps of DNA methylation and transcriptomes together with genomic DNA sequencing of 18 different primary human tissue types from 4 individuals are presented; analysis reveals widespread differential methylation of CG sites between tissues, and the presence of non-CG methylation in adult tissues.
Matthew D. Schultz, Yupeng He, John W. Whitaker et al. | Condensin-driven remodelling of X chromosome topology during dosage compensation
Genome-wide chromosome conformation capture analysis in C. elegans reveals that the dosage compensation complex, a condensin complex, remodels the X chromosomes of hermaphrodites into a sex-specific topology distinct from autosomes while regulating gene expression chromosome-wide.
Emily Crane, Qian Bian, Rachel Patton McCord et al. | | | | |
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