Mutations in SWI/SNF chromatin remodeling complex gene ARID1B cause Coffin-Siris syndrome

We identified de novo truncating mutations in ARID1B in three individuals with Coffin-Siris syndrome (CSS) by exome sequencing. Array-based copy-number variation (CNV) analysis in 2,000 individuals with intellectual disability revealed deletions encompassing ARID1B in 3 subjects with phenotypes partially overlapping that of CSS. Taken together with published data, these results indicate that haploinsufficiency of the ARID1B gene, which encodes an epigenetic modifier of chromatin structure, is an important cause of CSS and is potentially a common cause of intellectual disability and speech impairment.     

江苏省前三岛鸟类调查报告

前三岛由达念山岛、平山岛和车牛山岛三小岛组成，位于黄海，东经１１９°４９′１８″一１１９°５４′３０″、北纬３４°５９′４２″一３５°０８′２４″．岛上植被简单．据调查，前三岛鸟类１２９种，隶１５目３７科，其中非雀形目鸟类５１种，雀形目鸟类７８种，占总数的３９．５３％和６０．４７％．７３种为《中日候鸟保护协定》规定保护的鸟类．按动物地理区划，３１种属东洋界鸟类，８７种为古北界种类，广布１１种．按季节分．旅鸟５３种、冬候鸟２４种、夏候鸟３１种、留鸟２０种、迷鸟１种．有国家一级保护鸟１种，二级保护鸟１５种．黄蹼洋海燕是中国第一次发现的新记录．文中提出了有关保护鸟类的措施．     

Molecular basis of photoprotection and control of photosynthetic light-harvesting

In order to maximize their use of light energy in photosynthesis, plants have molecules that act as light-harvesting antennae, which collect light quanta and deliver them to the reaction centres, where energy conversion into a chemical form takes place. The functioning of the antenna responds to the extreme changes in the intensity of sunlight encountered in nature. In shade, light is efficiently harvested in photosynthesis. However, in full sunlight, much of the energy absorbed is not needed and there are vitally important switches to specific antenna states, which safely dissipate the excess energy as heat. This is essential for plant survival, because it provides protection against the potential photo-damage of the photosynthetic membrane. But whereas the features that establish high photosynthetic efficiency have been highlighted, almost nothing is known about the molecular nature of the dissipative states. Recently, the atomic structure of the major plant light-harvesting antenna protein, LHCII, has been determined by X-ray crystallography. Here we demonstrate that this is the structure of a dissipative state of LHCII. We present a spectroscopic analysis of this crystal form, and identify the specific changes in configuration of its pigment population that give LHCII the intrinsic capability to regulate energy flow. This provides a molecular basis for understanding the control of photosynthetic light-harvesting.     

Pitch discrimination in the minnow(Phoxinus laevis) at different temperature levels

Zusammenfassung Aus früheren Untersuchungen war bekannt, dass die Elritze (Phoxinus laevis) imstande ist, Töne nach ihrer Frequenz (Tonhöhe) zu unterscheiden, jedoch nur im Frequenzgebiet bis zu etwa 1260 Hz, nicht darüber (die obere Hörgrenze liegt bei etwa 5000 Hz). Es wurde geprüft, welchen Einfluss Wechsel der Temperatur auf die Lage dieser oberen Schwelle der Frequenzunterscheidung hat. Sie lag für die einzelnen Versuchstiere bei 16°C zwischen 800 und 1260 Hz; bei 25°C zwischen 1260 und 1420 Hz, also höher. Der Unterschied beruht nicht auf grösserer Lebhaftigkeit oder Reaktionsbereitschaft der Fische bei der höheren Temperatur. Das Ergebnis steht im Einklang mit der Vermutung, dass die Tonfrequenzunterscheidung bei Fischen nach dem «volley principle» (Wever) erfolgt.     

A low density of 0.8 g cm(-3) for the Trojan binary asteroid 617 Patroclus

The Trojan population consists of two swarms of asteroids following the same orbit as Jupiter and located at the L4 and L5 stable Lagrange points of the Jupiter-Sun system (leading and following Jupiter by 60 degrees ). The asteroid 617 Patroclus is the only known binary Trojan. The orbit of this double system was hitherto unknown. Here we report that the components, separated by 680 km, move around the system's centre of mass, describing a roughly circular orbit. Using this orbital information, combined with thermal measurements to estimate the size of the components, we derive a very low density of 0.8(- 0.1)+0.2 g cm(-3). The components of 617 Patroclus are therefore very porous or composed mostly of water ice, suggesting that they could have been formed in the outer part of the Solar System.     

The complete family of genes encoding G proteins of Caenorhabditis elegans

Caenorhabditis elegans is the first animal whose genomic sequence has been determined. One of the new possibilities in post-sequence genetics is the analysis of complete gene families at once. We studied the family of heterotrimeric G proteins. C. elegans has 20 Galpha, 2 Gbeta and 2 Ggamma genes. There is 1 homologue of each of the 4 mammalian classes of Galpha genes, G(i)/G(o)alpha, G(s)alpha , G(q)alpha and G12alpha, and there are 16 new alpha genes. Although the conserved Galpha subunits are expressed in many neurons and muscle cells, GFP fusions indicate that 14 new Galpha genes are expressed almost exclusively in a small subset of the chemosensory neurons of C. elegans. We generated loss-of-function alleles using target-selected gene inactivation. None of the amphid-expressed genes are essential for viability, and only four show any detectable phenotype (chemotaxis defects), suggesting extensive functional redundancy. On the basis of functional analysis, the 20 genes encoding Galpha proteins can be divided into two groups: those that encode subunits affecting muscle activity (homologues of G(i)/G(o)alpha, G(s)alpha and G(q)), and those (14 new genes) that encode proteins most likely involved in perception.     

Retrograde transport of endocytosed Shiga toxin to the endoplasmic reticulum.

Shiga toxin and some other protein toxins that act on targets in the cytosol have previously been shown to enter the trans-Golgi network. Transport by this route may be necessary for translocation of the toxin to the cytosol and for intoxication, but it is not known whether the enzymatically active part of the toxins actually enters the cytosol from the trans-Golgi network. It has been suggested that such toxins are transported in a retrograde manner to the endoplasmic reticulum and that translocation occurs in this organelle, but retrograde transport of endocytosed material beyond the trans-Golgi network has never been demonstrated. Here we show that in butyric acid-treated A431 cells endocytosed Shiga toxin is not only transported to the trans-Golgi network, but also to all Golgi stacks, to the endoplasmic reticulum and to the nuclear envelope. Furthermore, butyric acid sensitizes the cells to Shiga toxin, which is consistent with the possibility that retrograde transport is required for translocation of the toxin to the cytosol.     

相转移卡宾法合成2_甲基_2_戊烯酸

本文采用相转移卡宾法合成2-甲基-2-戊烯酸,收率为42.5‰,产品的香息较好,结果较佳.