Science News | October 10, 2007

# このところネタが多くて、翌日に先送りしたりしてます…あしからず

The Nobel Prize in Physics 2007

Press Release: The 2007 Nobel Prize in Physics

The Nobel Prize in Physics 2007 - Scientific Background

asahi.com： ノーベル物理学賞、巨大磁気抵抗効果発見の２氏に - サイエンス

ノーベル物理学賞、仏フェール氏と独グリュンベルク氏に : 科学 : YOMIURI ONLINE（読売新聞）

ノーベル物理学賞：仏フェール、独グリュンベルクの２氏に - 毎日ｊｐ(毎日新聞)

ノーベル物理学賞に「巨大磁気抵抗効果」の２博士　 - MSN産経ニュース

2007年ノーベル物理学賞は「GMR効果の発見」，独仏の2人が受賞 - 産業動向オブザーバ - Tech-On!

「GMR」発見者にノーベル物理学賞　大容量HDDを実現 - ITmedia News

ノーベル物理学賞、「ハードディスク大革命」をもたらした独仏2研究者に 国際ニュース : AFPBB News
　# ネタがネタだけにIT業界の食いつきがいいな

asahi.com： 謎のガンマ線、冬の雷雲から届く　東大など確認 - サイエンス

日本海側の冬の雷雲が40秒間放射した10 MeVガンマ線を初観測 | 独立行政法人 理化学研究所プレスリリース

Detection of high-energy gamma rays from winter thunderclouds.
H. Tsuchiya, T. Enoto, S. Yamada, T. Yuasa, M. Kawaharada, T. Kitaguchi, M. Kokubun, H. Kato, M. Okano, S. Nakamura, K. Makishima.
Physical Review Letters | doi:
　# 雷は電気だけじゃないんだ

異常たんぱく質の処理解明、アルツハイマー病治療に光明か : 科学 : YOMIURI ONLINE（読売新聞）

Two regulatory steps of ER-stress sensor Ire1 involving its cluster formation and interaction with unfolded proteins.
Yukio Kimata, Yuki Ishiwata-Kimata, Tatsuhiko Ito, Aiko Hirata, Tomohide Suzuki, Daisuke Oikawa, Masato Takeuchi, Kenji Kohno.
The Journal of Cell Biology 179, 75-86 (2007) | doi:10.1083/jcb.200704166

Chaperone protein BiP binds to Ire1 and dissociates in response to endoplasmic reticulum (ER) stress. However, it remains unclear how the signal transducer Ire1 senses ER stress and is subsequently activated. The crystal structure of the core stress-sensing region (CSSR) of yeast Ire1 luminal domain led to the controversial suggestion that the molecule can bind to unfolded proteins. We demonstrate that, upon ER stress, Ire1 clusters and actually interacts with unfolded proteins. Ire1 mutations that affect these phenomena reveal that Ire1 is activated via two steps, both of which are ER stress regulated, albeit in different ways. In the first step, BiP dissociation from Ire1 leads to its cluster formation. In the second step, direct interaction of unfolded proteins with the CSSR orients the cytosolic effector domains of clustered Ire1 molecules.

　# どうでもいいけど、Journal of Cell Biologyを「米科学誌セルバイオロジー」っていうのはどうかと思う

農業生物資源研究所：細胞の乾燥防ぐ遺伝子を発見 - 毎日ｊｐ(毎日新聞)

農業生物資源研究所 - プレスリリース - 生物の極限耐性のメカニズムに重要な役割を担う遺伝子の単離に世界で初めて成功

BIOCHEMISTRY: Surviving a Dry Spell.
Science 317, 296 (2007) | DOI: 10.1126/science.317.5836.296c

Trehalose transporter 1, a facilitated and high-capacity trehalose transporter, allows exogenous trehalose uptake into cells.
Takahiro Kikawada, Ayako Saito, Yasushi Kanamori, Yuichi Nakahara, Ken-ichi Iwata, Daisuke Tanaka, Masahiko Watanabe, Takashi Okuda.
PNAS 104, 11585-11590 (2007) | doi:10.1073/pnas.0702538104

Trehalose is potentially a useful cryo- or anhydroprotectant molecule for cells and biomolecules such as proteins and nucleotides. A major obstacle to application is that cellular membranes are impermeable to trehalose. In this study, we isolated and characterized the functions of a facilitated trehalose transporter [trehalose transporter 1 (TRET1)] from an anhydrobiotic insect, Polypedilum vanderplanki. Tret1 cDNA encodes a 504-aa protein with 12 predicted transmembrane structures. Tret1 expression was induced by either desiccation or salinity stress. Expression was predominant in the fat body and occurred concomitantly with the accumulation of trehalose, indicating that TRET1 is involved in transporting trehalose synthesized in the fat body into the hemolymph. Functional expression of TRET1 in Xenopus oocytes showed that transport activity was stereochemically specific for trehalose and independent of extracellular pH (between 4.0 and 9.0) and electrochemical membrane potential. These results indicate that TRET1 is a trehalose-specific facilitated transporter and that the direction of transport is reversible depending on the concentration gradient of trehalose. The extraordinarily high values for apparent Km (>100 mM) and Vmax (>500 pmol/min per oocyte) for trehalose both indicate that TRET1 is a high-capacity transporter of trehalose. Furthermore, TRET1 was found to function in mammalian cells, suggesting that it confers trehalose permeability on cells, including those of vertebrates as well as insects. These characteristic features imply that TRET1 in combination with trehalose has high potential for basic and practical applications in vivo.

　# 砂漠の復活人間とか…できません

筋委縮性側索硬化症、進行の仕組みを慶大教授ら解明 : 科学 : YOMIURI ONLINE（読売新聞）
　# 「英科学誌」でどうやって論文に辿り着けと？

3'-O-modified nucleotides as reversible terminators for pyrosequencing.
Jian Wu, Shenglong Zhang, Qinglin Meng, Huanyan Cao, Zengmin Li, Xiaoxu Li, Shundi Shi, Dae Hyun Kim, Lanrong Bi, Nicholas J. Turro, Jingyue Ju.
Proc. Natl. Acad. Sci. USA, Early Edition | doi:10.1073/pnas.0707495104

Pyrosequencing is a method used to sequence DNA by detecting the pyrophosphate (PPi) group that is generated when a nucleotide is incorporated into the growing DNA strand in polymerase reaction. However, this method has an inherent difficulty in accurately deciphering the homopolymeric regions of the DNA templates. We report here the development of a method to solve this problem by using nucleotide reversible terminators. These nucleotide analogues are modified with a reversible chemical moiety capping the 3'-OH group to temporarily terminate the polymerase reaction. In this way, only one nucleotide is incorporated into the growing DNA strand even in homopolymeric regions. After detection of the PPi for sequence determination, the 3'-OH of the primer extension products is regenerated through different deprotection methods. Using an allyl or a 2-nitrobenzyl group as the reversible moiety to cap the 3'-OH of the four nucleotides, we have synthesized two sets of 3'-O-modified nucleotides, 3'-O-allyl-dNTPs and 3'-O-(2-nitrobenzyl)-dNTPs as reversible terminators for pyrosequencing. The capping moiety on the 3'-OH of the DNA extension product is efficiently removed after PPi detection by either a chemical method or photolysis. To sequence DNA, templates containing homopolymeric regions are immobilized on Sepharose beads, and then extension–signal detection–deprotection cycles are conducted by using the nucleotide reversible terminators on the DNA beads to unambiguously decipher the sequence of DNA templates. Our results establish that this reversible-terminator-pyrosequencing approach can be potentially developed into a powerful methodology to accurately determine DNA sequences.

　# TH君、内容チェックね