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附上原文：# {/ }! R% u4 b: c6 m m0 i+ _
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ARTICLES
* I" `" }9 K: i. D+ v----------------------8 a; u' r) [0 F
Light-avoidance-mediating photoreceptors tile the Drosophila larval
$ Z @! \: {% a/ Cbody wall pp921 - 9261 `3 M# @5 M5 [% `: h4 O
Light sensing outside the eyes is common in many animals but is
6 q: @" A2 G: q5 ~5 N u1 F) P5 e; D9 ?usually confined to specialized organs. Here, the entire body wall of
! G% W, g% Q+ M* X4 {6 ]the fruitfly larva is found to be tiled with blue- and ultraviolet-
. p, H" w/ D3 C, `; d* xlight sensing neuronal dendrites, which are essential for the larva's 5 I2 l: y' `) A2 Z) {
innate light-avoidance behaviour. The phototransduction machinery used 3 ?0 I a( K' d4 J& c+ T! a$ D( L
by these neurons is distinct from other Drosophila photoreceptor 7 B( p- M8 e! R( H: Q1 ` T
molecules but similar to a system recently identified in nematode
7 f/ l ]0 z: k' _ o, uneurons.! H( L# I: j% \! S
Yang Xiang et al.
/ l( [( l' H( ]# ~# V* {$ c# xdoi:10.1038/nature09576
+ n4 T7 g' F% R8 g5 ?Abstract: http://www.nature.com/nature/jou ... bs/nature09576.html
% r# f- G- _. X8 L6 BArticle: http://www.nature.com/nature/jou ... ll/nature09576.html+ G- K1 P8 Z* Q5 D$ N0 y$ V
# v! j$ w* w! V5 k4 L9 U, @
TRIM24 links a non-canonical histone signature to breast cancer pp927
& L% `3 t D0 P' ^( I& L- 932$ p; `0 D; P* O6 t9 X- W1 G' f
A crystal structure of the tandem PHD and bromodomain regions of the
+ x) X F; k$ m4 P- ]. Jtranscription and chromatin regulator TRIM24 reveals combinatorial & w( J8 D& J! Q* {& J# m3 F5 M
recognition of dual marks on the histone H3 tail. TRIM24 is involved 6 `- I) l6 `7 `7 Z/ ~
in activation of oestrogen-dependent genes and is aberrantly expressed 6 I2 ]+ a" l' K9 k( A$ R, ~
in breast cancer.
* ? h0 ]9 w" x- R9 H8 i, w8 W1 gWen-Wei Tsai et al.
( e$ M- g V- o) s. N( |+ J9 Odoi:10.1038/nature09542
1 X( @7 j' O$ z+ A: E' u6 ^2 D" d1 TAbstract: http://www.nature.com/nature/jou ... bs/nature09542.html
4 K J" S& I+ K! PArticle: http://www.nature.com/nature/jou ... ll/nature09542.html
$ _/ f8 H5 Z' D: k+ F2 j# F4 [3 T! Y+ }, k
CRTC3 links catecholamine signalling to energy balance pp933 - 939
* @# ~: }8 M" B0 W* oβ-adrenergic receptor signalling in adipocytes stimulates energy 5 Q$ ]0 _# n" \$ D5 H2 {
expenditure via cAMP-dependent increases in lipolysis and fatty-acid
4 n: l/ ^% K6 I$ z( C0 V# ?, Roxidation, and this signalling mechanism is thought to be disrupted in : X. D- y# {+ h4 I% J
obesity. Here, the cAMP-responsive CREB coactivator Crtc3 is shown to % L4 T2 F% M# }" Z4 u* _0 _
promote obesity in mice by attenuating β adrenergic receptor
. c) A5 z+ k* D8 ?+ |0 _$ Gsignalling in adipose tissue.# J/ }8 S& ]' D9 G' n
Youngsup Song et al.
) `2 D& \7 R' Y& n- }3 M. Odoi:10.1038/nature09564
' }+ H. ?1 f- n$ I0 TAbstract: http://www.nature.com/nature/jou ... bs/nature09564.html4 B6 H" g3 O; |) D: n, P( K
Article: http://www.nature.com/nature/jou ... ll/nature09564.html
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# g+ i2 X% G& A# b& u% T( _LETTERS
! m7 T' e$ ^( k- ?. }# C+ o----------------------
6 X* U4 ] P; m8 |" `7 O! yA substantial population of low-mass stars in luminous elliptical
' _4 }* e/ W2 w0 s/ f2 h5 Lgalaxies pp940 - 9425 {- q7 f% J$ W5 Z
The stellar initial mass function describes the mass distribution of ' Z! P8 K- A' |% I4 q. l
stars at the time of their formation. This study reports observations 6 K% A! t ~( V( B7 J
of the Na I doublet and the Wing-Ford molecular FeH band in the - J D8 D3 \ N: n
spectra of elliptical galaxies. These lines are strong in stars with 5 e5 ^, ]0 i8 \2 e" A; n
masses
# b& {4 n( V6 r2 X- dPieter G. van Dokkum and Charlie Conroy) b8 \" y7 ^9 D9 l
doi:10.1038/nature09578
) f* L: @& L5 |! e+ gAbstract: http://www.nature.com/nature/jou ... bs/nature09578.html$ O( p3 U$ Z5 u# K
Article: http://www.nature.com/nature/jou ... ll/nature09578.html% [0 y3 C. v3 m5 n" `
* k+ O/ Z* A. b! y KOrigin of Saturn’s rings and inner moons by mass removal from a lost 9 u$ T$ E% C5 [+ |" v' u+ O
Titan-sized satellite p943
- g( A% d8 a7 t6 t2 i. n- F6 F2 YSaturn's rings are more than 90–95% water ice, which implies that
. T" ?, i) q2 s; ~" w u R1 ?( ginitially they were almost pure ice because they are continually
& t" V! z! P1 K" n( P2 N; dpolluted by rocky meteoroids. Saturn has only one large satellite,
* i# k4 @/ i; W+ F ATitan, whereas Jupiter has four large satellites; additional large 4 L- |' m( ~+ F0 F
satellites probably existed originally but were lost as they spiralled + n8 |; V4 H- }- H) ^& c* H ]
into Saturn. Now, numerical simulations of the tidal removal of mass 9 _/ i& u( {* R6 r/ ^
from a differentiated, Titan sized satellite as it migrates inward 4 t8 M8 r8 h9 k2 I& m1 t# G
towards Saturn are reported. Planetary tidal forces preferentially * V& U# M6 t) ~0 i/ \6 G; V. i' _& b
strip material from the satellite's outer icy layers, while its rocky 3 I1 p; ?) v9 b# B+ @" Z3 _' R
core remains intact and is lost to collision with the planet. The
+ ?9 g7 s7 x+ W+ ~8 H3 Vresult is a pure ice ring.
n5 `; s; N7 s0 f* H: s5 ^3 VRobin M. Canup3 F; @$ \1 Q) k! W
doi:10.1038/nature09661
' F6 G6 Y5 ^/ L4 iAbstract: http://www.nature.com/nature/jou ... bs/nature09661.html5 C, i; q8 p7 E
Article: http://www.nature.com/nature/jou ... ll/nature09661.html
2 T3 a7 \( q6 [- b- b- p- a% I
. O" Q& h; H. v! |0 W# h0 UPleats in crystals on curved surfaces pp947 - 951
2 D! H$ ]4 t5 nHexagons can easily tile a flat surface, but not a curved one. Defects
" ~" L, ]4 u7 w' ^7 Cwith topological charge (such as heptagons and pentagons) make it ' Z4 ~9 S! W$ y9 _$ ^0 g& I, ?
easier to tile curved surfaces, such as soccer balls. Here, a new type 6 C5 H+ q* ?& I; {4 w$ ?
of defect is reported that accommodates curvature in the same way as $ ]; v: ]- [: T7 e. B$ i
fabric pleats. The appearance of such defects on the negatively curved ' n! ], B6 d! }) r
surfaces of stretched colloidal crystals are observed. The results
9 H4 T5 V I& U- I4 l nwill facilitate the exploration of general theories of defects in
. _+ k3 E5 m0 p2 t) Ncurved spaces, the engineering of curved structures and novel methods 7 v8 b. M! r4 [! s5 ^6 k9 N- b/ P
for soft lithography and directed self-assembly.
% ^& V$ N) |3 o, G7 YWilliam T. M. Irvine, Vincenzo Vitelli and Paul M. Chaikin! `5 ~3 N0 \7 e3 w' }
doi:10.1038/nature096208 o# M$ Q! b% D: q
Abstract: http://www.nature.com/nature/jou ... bs/nature09620.html
0 d$ N8 \) T( _1 Y1 F/ ]( ?Article: http://www.nature.com/nature/jou ... ll/nature09620.html3 _! {. c- e& N" }( K, c X
8 _* z0 C$ a | y# I* X
Tidal dissipation and the strength of the Earth’s internal magnetic
3 N9 `5 T- \' _3 Xfield pp952 - 954, M% u2 f& R s5 G1 l- u
Here, an indirect estimate for the magnetic field strength within the / s7 j- o* X. v- e. [. I5 L
Earth's core from measurements of tidal dissipation is presented. # D& i2 ~4 s) `' r3 W% ?! [
Previously reported evidence of anomalous dissipation in the Earth's
% h- [6 i! }: I4 Y" i2 D. Rnutations can be explained with a core-averaged field of 2.5 mT,
" J* p6 W( v4 Z* C, g& k7 ~! Meliminating the need for high fluid viscosity or a stronger magnetic - _* U: g8 H' O) `
field at the inner-core boundary.1 J9 q# B: k% [7 C
Bruce A. Buffett6 H5 p K0 ?6 W! F: P3 g
doi:10.1038/nature09643
; u9 ~/ h& S( N. W9 t/ `Abstract: http://www.nature.com/nature/jou ... bs/nature09643.html; T* I$ i$ |: E2 I
Article: http://www.nature.com/nature/jou ... ll/nature09643.html6 _& @* c% t$ w0 W9 W7 e& r
2 }2 [2 p; d8 F, x- _
Greenhouse gas mitigation can reduce sea-ice loss and increase polar
0 i- d1 m" E2 z. O( {$ bbear persistence pp955 - 958. Z/ L5 ?: p- m0 F2 N0 @$ I$ f* e
The dramatic loss of Arctic sea ice with climate change has led to the 3 e. K) j5 X- k4 E( `) `: P1 Z
prediction of a tipping point beyond which ice loss is irreversible
0 {/ f4 f: L! Z# t) A3 jand polar bear habitat will be catastrophically lost. By contrast, 4 c3 \& \& V8 |: Z# j0 w V
this study shows a linear relationship between temperature and sea-ice + y* P4 C4 Y! t9 C. Y& I+ y4 a
coverage that overcomes the albedo effect that would cause a tipping
" e, o2 e! z! ~& g3 [. l' opoint. As a result, reducing greenhouse gas emissions can have a
0 D3 |) g' {7 w Jpositive effect on polar bear populations.6 F( r5 e9 G7 p1 G$ H6 [4 l
Steven C. Amstrup et al.
: o. {, Y/ M7 ^ a& G2 G& ~* R* Ndoi:10.1038/nature09653
0 G! j1 m/ C' o3 W! }& h+ x2 ?Abstract: http://www.nature.com/nature/jou ... bs/nature09653.html9 F* u! f2 e. Q% g F
Article: http://www.nature.com/nature/jou ... ll/nature09653.html' s$ A8 O4 C/ I3 \9 {
) F7 J2 k$ k" I( @: T+ r; V
Intercalation of a new tier of transcription regulation into an
+ Q, d/ p4 Z5 M1 G7 kancient circuit pp959 - 963
5 b2 ?& S+ ^4 i1 PHow new phenotypes can be introduced during evolution without losses
; V+ l& N( }% f, \ u5 }5 Oof fitness remains largely unexplained at the molecular level. By . ~6 c( N+ H2 V* u" i, H0 {; C/ U
comparing the molecular details of a well known process — mating type , X/ J9 G) M. _% H
determination — across a large diversity of yeast species, the - B7 W$ k# a7 t. y; W3 ]7 d# M% x& r
network rewiring event of the intercalation of a new level of gene 7 m# m& c J( Y2 O- w
transcription control into an ancient regulatory circuit is shown, 6 V9 E9 S5 G! w) n3 K. _ e+ t& {0 ~
which allowed for the creation of a new phenotype — taking food 8 q Y* T$ P# t2 [/ w1 a/ V, n: i* N
availability into account when deciding to mate.
9 y4 \% ~. v* Q/ e( f9 b0 X6 ZLauren N. Booth, Brian B. Tuch and Alexander D. Johnson
+ L0 w# V$ B' k: F6 A! ydoi:10.1038/nature09560
! `# K* y9 H8 OAbstract: http://www.nature.com/nature/jou ... bs/nature09560.html/ t& [# U6 f# P+ I. L
Article: http://www.nature.com/nature/jou ... ll/nature09560.html; m, d0 {& @+ @8 t
' ?- J6 M8 K' d1 L8 lNoise correlations improve response fidelity and stimulus encoding
9 C6 s$ j2 x3 g5 P7 ~4 Epp964 - 967
/ Z8 U2 l6 a& hThis study introduces a novel recording technique for simultaneously ! f$ v" B" |) _' X+ A8 S
measuring excitatory and inhibitory conductances of retinal ganglion
1 c; n5 z7 @) r w9 @cells to show that excitatory and inhibitory inputs are strongly
" e/ c; }7 u. |" ^- P: Rcorrelated, thereby cancelling each other. Furthermore, dynamic clamp : q3 X# y& v# _" i C
is used to introduce these conductance changes into the cell with or % h/ i. d1 P: S3 F, M9 x7 l
without correlations, and it is found that, as predicted by / c9 J6 M% r, q- E
theoretical work, correlations significantly increase reliability of 9 ^, x1 X# r$ j" F. E# K
the spiking response.) _3 H) N/ k' Y
Jon Cafaro and Fred Rieke' g! E! j6 R3 e' L7 x
doi:10.1038/nature09570* M+ @. A' b0 D* g. O& s- A
Abstract: http://www.nature.com/nature/jou ... bs/nature09570.html
1 U: [8 J& J+ ?6 tArticle: http://www.nature.com/nature/jou ... ll/nature09570.html
+ P/ N8 n0 ~) Q1 K2 K& f1 k1 f
0 Z% {/ f' n1 \COT drives resistance to RAF inhibition through MAP kinase pathway . \0 Y9 j! h2 a
reactivation pp968 - 972
: M. y5 C7 l+ \5 C, BRecent data from early clinical trials in melanoma patients carrying ; b- R# {" ` P" b. m
mutations in the B-RAF gene have shown promising results with the B-
# Z$ \/ n+ _* g a- ?RAF kinase inhibitor PLX4032; however, many patients eventually
, G6 x: k/ L$ Xdevelop resistance to this treatment. Two papers now uncover possible 3 p F+ G; p: J3 P
mechanisms of resistance to PLX4032. One paper shows that upregulation 6 S1 P5 _$ f; n" N
of MAP3K8 (which encodes COT) can confer resistance of melanoma cells 5 E2 P. M3 ?" u0 p2 D o& l
to B-RAF inhibitors, whereas another paper found that melanomas can 2 F! h# t( E' ~/ `8 S
acquire resistance due to mutations of N-RAS or increased expression ' {) p! j: _9 x( B5 e$ K" l7 v9 F
of PDGFRβ. Each of these resistance mechanisms seems to apply to at
. L- U9 R) w" H( \$ h/ x: Cleast some patients on recent PLX4032 trial, whereas, surprisingly, so
9 [! V/ X2 r3 G& l( {+ L: Wfar no secondary B-RAF mutations have been observed.
8 s6 G8 S9 t/ v% Q' F8 h6 wCory M. Johannessen et al.
% R% @* P' m) @+ y7 ^doi:10.1038/nature09627
9 F* @/ E/ `$ G, E4 e+ \& gAbstract: http://www.nature.com/nature/jou ... bs/nature09627.html6 H, e7 D8 d: I6 J* X D7 ?. x
Article: http://www.nature.com/nature/jou ... ll/nature09627.html& S5 J( H. `. u4 E
" T1 V# K; I# d- NMelanomas acquire resistance to B-RAF(V600E) inhibition by RTK or N-
; `/ J8 _) `; M2 }) |0 SRAS upregulation pp973 - 977
8 T3 s, X/ o# J6 rRecent data from early clinical trials in melanoma patients carrying
: w8 z/ b4 K) T4 w% X; umutations in the B-RAF gene have shown promising results with the B-
' G2 v9 ~4 {- Y2 U% a/ M8 YRAF kinase inhibitor PLX4032; however, many patients eventually ; i: b/ d0 |. r3 _4 z( b/ D
develop resistance to this treatment. Two papers now uncover possible - e- R7 P5 Z# x, F! l) b& L& a& @
mechanisms of resistance to PLX4032. One paper shows that upregulation
" U1 ?2 P3 H& l* K: Q( I, ^( Nof MAP3K8 (which encodes COT) can confer resistance of melanoma cells
- n" K5 r+ C1 } o; Uto B-RAF inhibitors, whereas another paper found that melanomas can
$ }4 @5 b+ Z+ O) E0 yacquire resistance due to mutations of N-RAS or increased expression 0 a% R1 ~' ^! z4 y% e: d# u
of PDGFRβ. Each of these resistance mechanisms seems to apply to at
' N: l/ P0 c, r3 N. E# cleast some patients on recent PLX4032 trial, whereas, surprisingly, so
9 [) c. [* s; n/ l2 q3 s% C- kfar no secondary B-RAF mutations have been observed.' i- Y% y# O& q3 n: m
Ramin Nazarian et al.+ a. M' {. w4 i) {6 B0 n* B
doi:10.1038/nature09626+ g( Y' T* U: D. x/ m
Abstract: http://www.nature.com/nature/jou ... bs/nature09626.html
0 @* l. I* S+ h3 N1 g1 MArticle: http://www.nature.com/nature/jou ... ll/nature09626.html! {( o6 D# E: t: y3 H& L7 K! l
- P! F/ g# n) b8 _2 t: K; p
Crystal structure of bacterial RNA polymerase bound with a
. i2 g! p1 J) \. h+ N* T& U8 Ztranscription inhibitor protein pp978 - 982
: G- f- z! R. o) YA crystal structure of bacterial RNA polymerase (RNAP) bound to the
) i2 w/ w9 V: t+ D5 itranscription inhibitor Gfh1 reveals the mechanism of inhibition by 3 d0 D7 Z+ {0 Q l8 s, a
Gfh1 and an alternative ratcheted state of RNAP.
, f+ A4 U7 a: e! U- p( h# PShunsuke Tagami et al., I: m% P4 a, r
doi:10.1038/nature09573
8 k6 X! m. v: WAbstract: http://www.nature.com/nature/jou ... bs/nature09573.html; p: p" h6 y! e, V% a
Article: http://www.nature.com/nature/jou ... ll/nature09573.html% U% V/ t1 F4 k8 G
4 _' |7 @' Y. J" }/ qSingle-molecule imaging reveals mechanisms of protein disruption by a * y8 T! F% K5 ?- b2 l
DNA translocase pp983 - 987; q/ f% {" ~" W/ }6 L [
Protein machineries that move along the DNA, such as DNA polymerases # X( h& p( g9 y$ N
and helicases, will necessarily encounter other bound proteins
3 `/ C" _ ]* o0 c# j& `( zinteracting with specific sites. Using 'curtains' of labelled DNA, 0 Z7 D$ a4 u* W" Z; t
this study measured whether such bound proteins interfere with the
& ~! o6 L# g, z0 h1 D, oactivity of the bacterial DNA translocase RecBCD. The translocase is & x7 r5 ~0 O- Z0 Y& M
able to push the proteins over nonspecific sites for thousands of base
& Z* F$ H9 F; h) D" A1 ypairs before they are displaced.2 w3 d6 w `: S# g
Ilya J. Finkelstein, Mari-Liis Visnapuu and Eric C. Greene2 O% h& @$ t9 x1 h) H8 a: ?" c
doi:10.1038/nature09561
# |, f" H( B. ]: r I& MAbstract: http://www.nature.com/nature/jou ... bs/nature09561.html
& H# p0 F% Q1 a P7 |0 aArticle: http://www.nature.com/nature/jou ... ll/nature09561.html
. t9 `5 m4 F" E+ {9 p
- d: I8 h+ ]+ NThe mechanism of sodium and substrate release from the binding pocket . w! @; T& S. m" I
of vSGLT pp988 - 991: z" D- d: E' b2 C2 p
Here, a comprehensive study of the sodium/galactose transporter ' q7 h8 I/ C7 P9 e& m
(vSGLT) is presented, consisting of molecular dynamics simulations,
! F/ F G- M5 J4 x7 dbiochemical characterization and a new crystal structure of the 3 a f( X5 P2 {7 p# [; Q! V
'inward-open' conformation. These experiments show that sodium exit
# r# Z% z' t z7 }$ bcauses a reorientation of transmembrane helix 1, opening an inner gate 6 ]/ q( w% v4 X* G: f
required for substrate exit, while also triggering minor rigid-body 5 x! n5 ?2 w8 K. S5 X
movements in two sets of transmembrane helical bundles. This cascade 2 m- s$ d4 `; c& z" j( C
of conformational changes is responsible for the proper timing of ion ( q Q( x6 U5 k) y" g* ^. o
and substrate release. |
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发表于 2010-12-16 16:18
非常好 谢谢楼主
发表于 2010-12-17 10:30
