| | Cell biology: Polarized transport in the Golgi apparatus
Proteins can be transported in either direction across a cellular organelle called the Golgi apparatus. It emerges that CDC42, a molecule that confers cell polarity, acts to control the directionality of transport in the Golgi.
| Evolution: Steps on the road to eukaryotes
A new archaeal phylum represents the closest known relatives of eukaryotes, the group encompassing all organisms that have nucleated cells. The discovery holds promise for a better understanding of eukaryotic origins.
| An alternative pluripotent state confers interspecies chimaeric competency
A previously unknown type of stem cell that can engraft in specific regions of the mouse epiblast is described; these region-selective pluripotent stem cells display notable intra- and inter-specific chimaera competency and will help to further our understanding of mammalian development.
| Complex archaea that bridge the gap between prokaryotes and eukaryotes
This study identifies a clade of archaea that is the immediate sister group of eukaryotes in phylogenetic analyses, and that also has a repertoire of proteins otherwise characteristic of eukaryotes—proteins that would have provided the first eukaryotes with a 'starter kit' for the genomic and cellular complexity characteristic of the eukaryotic cell.
| Epicardial regeneration is guided by cardiac outflow tract and Hedgehog signalling
Using a genetic approach in zebrafish, the mesothelial covering of the heart—the epicardium—is shown to have a high regenerative ability after injury, a process that is driven by Hedgehog signalling originating from the outflow tract.
| Histone H3.3 is required for endogenous retroviral element silencing in embryonic stem cells
Transposable elements in mammalian genomes need to be silenced to avoid detrimental genome instability; here, the histone variant H3.3 is shown to have an important role in silencing endogenous retroviral elements.
| Synthesis and applications of RNAs with position-selective labelling and mosaic composition
A hybrid solid–liquid phase transcription method and automated robotic platform synthesizes position-specific, fluorescence- or isotope-labelled RNA.
| Coordinated regulation of bidirectional COPI transport at the Golgi by CDC42
The COPI complex, which has a role in retrograde transport through the Golgi, is shown to also mediate anterograde tubular transport through the Golgi; in response to external stimuli, the small GTPase CDC42 acts as an essential modulator of bidirectional Golgi transport, and promotes the sorting of cargoes destined for anterograde transport into the tubules at the expense of those targeted for retrograde transport.
| 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.
| | Curtain eruptions from Enceladus' south-polar terrain
Observations of the south pole of the Saturnian moon Enceladus revealed large rifts in the terrain that were found to be the sources of the observed jets of water vapour; now it is shown that much of the eruptive activity can be explained by broad, curtain-like eruptions, many of which were probably misinterpreted previously as discrete jets.
Joseph N. Spitale, Terry A. Hurford, Alyssa R. Rhoden et al. | A direct GABAergic output from the basal ganglia to frontal cortex
Anatomical and functional analyses reveal the existence of two types of globus pallidus externus neurons that directly control cortex, suggesting a pathway by which dopaminergic drugs used to treat neuropsychiatric disorders may act in the basal ganglia to modulate cortex.
Arpiar Saunders, Ian A. Oldenburg, Vladimir K. Berezovskii et al. | A bizarre Jurassic maniraptoran theropod with preserved evidence of membranous wings
A recently discovered fossil belonging to the Scansoriopterygidae, a group of bizarre dinosaurs closely related to birds, represents a new scansoriopterygid species and preserves evidence of a membranous aerodynamic surface very different from a classic avian wing.
Xing Xu, Xiaoting Zheng, Corwin Sullivan et al. | An extremely young massive clump forming by gravitational collapse in a primordial galaxy
An extremely young star-forming region caught at gravitational collapse in a distant galaxy is shedding new light on the processes driving galaxy growth in the early Universe.
A. Zanella, E. Daddi, E. Le Floc'h et al. | Immunosuppressive plasma cells impede T-cell-dependent immunogenic chemotherapy
IgA plasmocytes are shown to promote resistance to the immunogenic chemotherapeutic oxaliplatin in prostate cancer mouse models by inhibiting activation of cytotoxic T cells; immunosuppressive plasma cells, which are also found in human-therapy-resistant prostate cancer, are generated in response to TGFβ, and their functionality depends on PD-L1 expression and IL-10 secretion.
Shabnam Shalapour, Joan Font-Burgada, Giuseppe Di Caro et al. | The formation and fate of internal waves in the South China Sea
Internal oceanic waves are subsurface gravity waves that can be enormous and travel thousands of kilometres before breaking but they are difficult to study; here observations of such waves in the South China Sea reveal their formation mechanism, extreme turbulence, relationship to the Kuroshio Current and energy budget.
Matthew H. Alford, Thomas Peacock, Jennifer A. MacKinnon et al. | Seed coating with a neonicotinoid insecticide negatively affects wild bees
Neonicotinoid seed coating is associated with reduced density of wild bees, as well as reduced nesting of solitary bees and reduced colony growth and reproduction of bumblebees, but appears not to affect honeybees.
Maj Rundlöf, Georg K. S. Andersson, Riccardo Bommarco et al. | Training and operation of an integrated neuromorphic network based on metal-oxide memristors
A transistor-free metal-oxide memristor crossbar with low device variability is realised and trained to perform a simple classification task, opening the way to integrated neuromorphic networks of a complexity comparable to that of the human brain, with high operational speed and manageable power dissipation.
M. Prezioso, F. Merrikh-Bayat, B. D. Hoskins et al. | Bees prefer foods containing neonicotinoid pesticides
It has been suggested that the negative effects on bees of neonicotinoid pesticides could be averted in field conditions if they chose not to forage on treated nectar; here field-level neonicotinoid doses are used in laboratory experiments to show that honeybees and bumblebees do not avoid neonicotinoid-treated food and instead actually prefer it.
Sébastien C. Kessler, Erin Jo Tiedeken, Kerry L. Simcock et al. | Differential DNA mismatch repair underlies mutation rate variation across the human genome
An analysis of how regional mutation rates vary across 652 tumours identifies variable DNA mismatch repair as the basis of the characteristic regional variation in mutation rates seen across the human genome; the results show that differential DNA repair, rather than differential mutation supply, is likely to be the primary cause of this variation.
Fran Supek, Ben Lehner | Vertically transmitted faecal IgA levels determine extra-chromosomal phenotypic variation
Microbially driven dichotomous faecal immunoglobulin-A levels in wild-type mice within the same facility mimic the effects of chromosomal mutations, indicating that phenotypic comparisons between mice must take into account the non-chromosomal hereditary variation between different breeders.
Clara Moon, Megan T. Baldridge, Meghan A. Wallace et al. | Allogeneic IgG combined with dendritic cell stimuli induce antitumour T-cell immunity
Naturally occurring tumour-binding IgG antibodies are shown to initiate the rejection of allogeneic tumours, whereby Fc-receptor-mediated uptake of tumour immune complexes into dendritic cells activates tumour-reactive T cells, and intra-tumoral injection of allogeneic IgG together with dendritic cell adjuvants induces systemic T-cell-mediated antitumour responses.
Yaron Carmi, Matthew H. Spitzer, Ian L. Linde et al. | X-domain of peptide synthetases recruits oxygenases crucial for glycopeptide biosynthesis
Glycopeptide antibiotics are biosynthesized by non-ribosomal peptide synthetases, which contain a previously uncharacterized 'X-domain' now shown to recruit three cytochrome P450 oxygenases that are necessary for the antibiotics to achieve their final, active conformation.
Kristina Haslinger, Madeleine Peschke, Clara Brieke et al. | | | | |
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