Table of Contents

Volume 517 Number 7532 pp6-116

1 January 2015

About the cover

Dunes on Titan in a Cassini radar mapper image taken on 21 December 2008 (upper part of image) resemble those in Conception Bay in the Namib desert, seen here from 283 km altitude in NASA crew image STS107-E-5380 (lower part of image). NASA’s Cassini spacecraft mission — still out there sending data from the Saturnian system — has revealed extensive aeolian (wind-formed) dunes on the surface of Titan, Saturn’s largest satellite. Devon Burr et al. used a high-pressure wind tunnel to simulate the thick near-surface atmosphere on Titan and, with numerical modelling of the low gravity and low sediment density, derived the wind speeds necessary to move dune sand on Titan. These speeds are significantly higher than those predicted by present models of sediment entrainment by wind that are based on wind-tunnel experiments under conditions relevant for Earth and Mars. Experimental results and theoretical work can be reconciled if the extremely low ratio of particle to fluid density on Titan is taken into account, a correction that is not required for high density ratio environments such as jets on comets. Cover: NASA/JPL-Caltech/ASI/ Johnson Space Center

This Week


  • Time for the social sciences

    Governments that want the natural sciences to deliver more for society need to show greater commitment towards the social sciences and humanities.

World View


    News in Focus


    • Science in 2015

      No Alt text available for this image

      From Gradzilla to coffee consumption: the research enterprise quantified for the year to come.

      • Mark Zastrow


    Books and Arts

    • Listings: Science in culture 2015

      Explore the gory glories of forensic science, grapple with Tom Stoppard's take on consciousness, learn what it takes to live on Mars, re-enter Jurassic Park, dive into a coral reef and dally with Robert Oppenheimer. Daniel Cressey reports.

      • Review of Oppenheimer, Countdown to Zero: Defeating Disease, Imagine Science Films, Forensics: The Anatomy of Crime, Emerge, Arsenic and New Medicine: Paul Ehrlich's Pioneering Research, EXPO 2015, Jurassic World, Coral Reefs: Secret Cities of the Sea, A Brief History of the Future, The Martian, The Hard Problem, Designers in Residence 2015: Migration, It's Alive! — Frankenstein on Film, Marvellous Creatures, Frida Kahlo’s Garden, Lava & The Francis Crick Institute





    • Hopes for the year ahead

      To kick off 2015, Nature's Careers section asked several young scientists — all 40 or under — about their plans for the year ahead and their wishes for the future of science.

      • Monya Baker

    naturejobs job listings and advertising features







    • RNA regulons in Hox 5′ UTRs confer ribosome specificity to gene regulation

      • Shifeng Xue
      • Siqi Tian
      • Kotaro Fujii
      • Wipapat Kladwang
      • Rhiju Das
      • Maria Barna

      Specialized ribosomes (with a particular protein composition) carry out translation of specific transcripts; analysis of Hox mRNA translation in mice reveals that unique RNA structural elements within their 5′ UTRs, including internal ribosome entry sites and translation inhibitory elements, are responsible for this specialized mode of translation.

      See also
    • Architecture and conformational switch mechanism of the ryanodine receptor

      • Rouslan G. Efremov
      • Alexander Leitner
      • Ruedi Aebersold
      • Stefan Raunser

      Using electron cryomicroscopy, the structure of the rabbit RyR1 calcium channel is determined at 6.1 Å resolution in the closed state and 8.5 Å in the open state, revealing how calcium binding to the EF-hand of RyR1 regulates channel opening and facilitates calcium-induced calcium release.

    • Structure of a mammalian ryanodine receptor

      • Ran Zalk
      • Oliver B. Clarke
      • Amédée des Georges
      • Robert A. Grassucci
      • Steven Reiken
      • Filippo Mancia
      • Wayne A. Hendrickson
      • Joachim Frank
      • Andrew R. Marks

      Using electron cryomicroscopy, the closed-state structure of rabbit RyR1 is determined at 4.8 Å resolution; analysis confirms that the RyR1 architecture consists of a six-transmembrane ion channel with a cytosolic α-solenoid scaffold, and suggests a mechanism for Ca2+-induced channel opening.

    • Structure of the rabbit ryanodine receptor RyR1 at near-atomic resolution

      • Zhen Yan
      • Xiao-chen Bai
      • Chuangye Yan
      • Jianping Wu
      • Zhangqiang Li
      • Tian Xie
      • Wei Peng
      • Chang-cheng Yin
      • Xueming Li
      • Sjors H. W. Scheres
      • Yigong Shi
      • Nieng Yan

      Using electron cryomicroscopy, the structure of the closed-state rabbit ryanodine receptor RyR1 in complex with its modulator FKBP12 is solved at 3.8 Å; in addition to determining structural details of the ion-conducting channel domain, three previously uncharacterized domains help to reveal a molecular scaffold that allows long-range allosteric regulation of channel activities.


    • A higher-than-predicted measurement of iron opacity at solar interior temperatures

      • J. E. Bailey
      • T. Nagayama
      • G. P. Loisel
      • G. A. Rochau
      • C. Blancard
      • J. Colgan
      • Ph. Cosse
      • G. Faussurier
      • C. J. Fontes
      • F. Gilleron
      • I. Golovkin
      • S. B. Hansen
      • C. A. Iglesias
      • D. P. Kilcrease
      • J. J. MacFarlane
      • R. C. Mancini
      • S. N. Nahar
      • C. Orban
      • J.-C. Pain
      • A. K. Pradhan
      • M. Sherrill
      • B. G. Wilson

      Laboratory measurements of iron opacity made under conditions similar to those inside the Sun reveal much higher opacity than predicted, helping to resolve inconsistencies within stellar models of the internal temperatures of stars.

    • Higher-than-predicted saltation threshold wind speeds on Titan

      • Devon M. Burr
      • Nathan T. Bridges
      • John R. Marshall
      • James K. Smith
      • Bruce R. White
      • Joshua P. Emery

      Wind tunnel experiments designed to simulate the conditions on Saturn’s moon Titan yield threshold wind speeds for particle saltation higher than those predicted by models derived from simulations of terrestrial-planet conditions; the results can be reconciled by modifying the models to take into account the low ratio of particle density to fluid density on Titan.

    • Observation of quantized conductance in neutral matter

      • Sebastian Krinner
      • David Stadler
      • Dominik Husmann
      • Jean-Philippe Brantut
      • Tilman Esslinger

      Quantized conductance in the transport of neutral atoms is observed in an optically produced channel — either a quantum point contact or a quantum wire — between two atom reservoirs; the lowest non-zero conductance value is the universal conductance quantum, the reciprocal of Planck’s constant.

    • An anisotropic hydrogel with electrostatic repulsion between cofacially aligned nanosheets

      • Mingjie Liu
      • Yasuhiro Ishida
      • Yasuo Ebina
      • Takayoshi Sasaki
      • Takaaki Hikima
      • Masaki Takata
      • Takuzo Aida

      Usually materials design focuses on attractive interactions, but here a hydrogel is described whose properties are dominated by electrostatic repulsion between negatively charged titanate nanosheets embedded within it; the material, inspired by articular cartilage, deforms easily when sheared parallel to the sheets but resists compressive forces applied orthogonally.

      See also
    • Strong and deep Atlantic meridional overturning circulation during the last glacial cycle

      • E. Böhm
      • J. Lippold
      • M. Gutjahr
      • M. Frank
      • P. Blaser
      • B. Antz
      • J. Fohlmeister
      • N. Frank
      • M. B. Andersen
      • M. Deininger

      Reconstruction of the Atlantic meridional overturning circulation from a highly resolved marine sedimentary record shows that a deep, vigorous overturning circulation mode has persisted for most of the last glacial cycle, dominating ocean circulation in the Atlantic, but that a shallower glacial mode prevailed during glacial maxima.

      See also
    • Origins of major archaeal clades correspond to gene acquisitions from bacteria

      • Shijulal Nelson-Sathi
      • Filipa L. Sousa
      • Mayo Roettger
      • Nabor Lozada-Chávez
      • Thorsten Thiergart
      • Arnold Janssen
      • David Bryant
      • Giddy Landan
      • Peter Schönheit
      • Bettina Siebers
      • James O. McInerney
      • William F. Martin

      A comparison of protein-coding genes from 134 archaeal genomes with their homologues in 1,847 bacterial genomes reveals that, during evolution, genes are transferred more often from bacteria to archaea than vice versa, and that gene influxes from bacteria can bring about the origin of major archaeal groups.

    • Hepatitis A virus and the origins of picornaviruses

      • Xiangxi Wang
      • Jingshan Ren
      • Qiang Gao
      • Zhongyu Hu
      • Yao Sun
      • Xuemei Li
      • David J. Rowlands
      • Weidong Yin
      • Junzhi Wang
      • David I. Stuart
      • Zihe Rao
      • Elizabeth E. Fry

      Hepatitis A virus is a picornavirus that causes significant morbidity but remains poorly understood; this paper now provides high-resolution crystal structures of both the mature and the empty hepatitis A virus particle, which show that the three-dimensional structure resembles insect picorna-like viruses.

    • Human intracellular ISG15 prevents interferon-α/β over-amplification and auto-inflammation

      • Xianqin Zhang
      • Dusan Bogunovic
      • Béatrice Payelle-Brogard
      • Véronique Francois-Newton
      • Scott D. Speer
      • Chao Yuan
      • Stefano Volpi
      • Zhi Li
      • Ozden Sanal
      • Davood Mansouri
      • Ilhan Tezcan
      • Gillian I. Rice
      • Chunyuan Chen
      • Nahal Mansouri
      • Seyed Alireza Mahdaviani
      • Yuval Itan
      • Bertrand Boisson
      • Satoshi Okada
      • Lu Zeng
      • Xing Wang
      • Hui Jiang
      • Wenqiang Liu
      • Tiantian Han
      • Delin Liu
      • Tao Ma
      • Bo Wang
      • Mugen Liu
      • Jing-Yu Liu
      • Qing K. Wang
      • Dilek Yalnizoglu
      • Lilliana Radoshevich
      • Gilles Uzé
      • Philippe Gros
      • Flore Rozenberg
      • Shen-Ying Zhang
      • Emmanuelle Jouanguy
      • Jacinta Bustamante
      • Adolfo García-Sastre
      • Laurent Abel
      • Pierre Lebon
      • Luigi D. Notarangelo
      • Yanick J. Crow
      • Stéphanie Boisson-Dupuis
      • Jean-Laurent Casanova
      • Sandra Pellegrini

      ISG15 deficiency in humans leads to a failure to maintain adequate levels of USP18, triggering an increase in type I interferon production and signalling, and promoting auto-inflammatory disease.

    • A PP1–PP2A phosphatase relay controls mitotic progression

      • Agnes Grallert
      • Elvan Boke
      • Anja Hagting
      • Ben Hodgson
      • Yvonne Connolly
      • John R. Griffiths
      • Duncan L. Smith
      • Jonathon Pines
      • Iain M. Hagan

      The activation and coordination of phosphatase activity is important during mitotic exit; here, a mitotic phosphatase relay is described in fission yeast between the two major phosphatases, PP1 and PP2A, a mode of regulation that may be a feature of signalling networks across eukaryotes.

      See also
    • Native structure of photosystem II at 1.95 Å resolution viewed by femtosecond X-ray pulses

      • Michihiro Suga
      • Fusamichi Akita
      • Kunio Hirata
      • Go Ueno
      • Hironori Murakami
      • Yoshiki Nakajima
      • Tetsuya Shimizu
      • Keitaro Yamashita
      • Masaki Yamamoto
      • Hideo Ago
      • Jian-Ren Shen

      The radiation-damage-free structure of the photosystem II membrane protein complex, which oxidizes water into dioxygen in an oxygen evolving complex, has been determined by an X-ray free electron laser at a resolution of 1.95 Å; one of the substrate oxygen atoms in this reaction is now identified.

      See also
    • Structure of an integral membrane sterol reductase from Methylomicrobium alcaliphilum

      • Xiaochun Li
      • Rita Roberti
      • Günter Blobel

      Solving the X-ray crystal structure of a Δ14-sterol reductase and homologue of human C14SR and DHCR7, two enzymes that reduce specific carbon–carbon double bonds in the cholesterol biosynthetic pathway, may provide insight into how specific mutations in DHCR7 and lamin B receptor lead to human diseases.