pages 1212 & 1221
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www.sciencemag.org SCIENCE VOL 343 14 MARCH 2014
1215 Structures of Cas9 Endonucleases Reveal
RNA-Mediated Conformational Activation
M. Jinek et al.
Binding of a guide RNA triggers structural
changes in a set of DNA-cleaving enzymes.
Research Article Summary; for full text:
1216 Ligand-Controlled C(sp3)–H Arylation
and Olefination in Synthesis of Unnatural
Chiral α–Amino Acids
J. He et al.
Two different ligands can be used in
succession to tune the reactivity of a
1221 Specific and Nonhepatotoxic Degradation
of Nuclear Hepatitis B Virus cccDNA
J. Lucifora et al.
Cytokine induction renders viral DNA
vulnerable and eliminates infection.
>> Perspective p. 1212
1228 Free-Standing Single-Atom-Thick Iron
Membranes Suspended in Graphene Pores
J. Zhao et al.
The pores in a graphene membrane stabilize the
formation of two-dimensional iron sheets.
1232 Main-Group Compounds Selectively
Oxidize Mixtures of Methane, Ethane,
and Propane to Alcohol Esters
B. G. Hashiguchi et al.
Lead and thallium salts are surprisingly
selective and efficient oxidants of the
constituents of natural gas.
1237 Changes in Seismic Anisotropy Shed Light on
the Nature of the Gutenberg Discontinuity
C. Beghein et al.
The Gutenberg discontinuity is distinct from
the lithosphere-asthenosphere boundary.
1240 Lethal Interactions Between Parasites
and Prey Increase Niche Diversity in a
M. A. Condon et al.
Incorrect fly-host choice in parasitoid wasps
creates multidimensional niches, generating
high levels of hidden diversity.
>> Perspective p. 1213
1244 Structure of Human RNase L Reveals
the Basis for Regulated RNA Decay in
the IFN Response
Y. Han et al.
The crystal structure of an interferon-induced
ribonuclease shows how it selects and shreds
its RNA targets.
1249 Selective Methylation of Histone H3 Variant
H3.1 Regulates Heterochromatin Replication
Y. Jacob et al.
The specificity of a histone methyltransferase
for a histone variant maintains heterochromatin
through cell division.
1253 Vertebrate Limb Bud Formation Is Initiated
by Localized Epithelial-to-Mesenchymal
J. Gros and C. J. Tabin
Cell state change, rather than differential
proliferation, initiates limb formation
1256 The stum Gene Is Essential for Mechanical
Sensing in Proprioceptive Neurons
B. S. Desai et al.
The stumble gene in flies is required in
neurons that sense joint angles.
1260 Complement Is Activated by IgG Hexamers
Assembled at the Cell Surface
C. A. Diebolder et al.
Hexameric platforms of antibodies on the cell
surface trigger the complement cascade.
1264 Dlk1 Promotes a Fast Motor Neuron
Biophysical Signature Required for Peak
D. Müller et al.
The fast versus slow profile of motor neurons is
controlled by expression of a membrane protein.