autophagy(自食作用)の仕組みを解明した東工大 大隅良典栄誉教授がノーベル医学・生理学賞をめでたく受賞しました。日本人のノーベル賞受賞は3年連続で、日本人ノーベル賞受賞者数が25人になったそうです(アメリカ国籍を取得した人も含めて)。日本人スゲーと言いたくなりますが、凄いのはほんの一握りの日本人だけです。




Medicine Nobel Recognizes “Self-Eating” Cells

The 2016 Nobel Prize in Medicine or Physiology was awarded to Yoshinori Ohsumi of the Tokyo Institute of Technology for basic research describing a fundamental housekeeping function of the cell—a process called autophagy. From the Greek for “self-eating,” autophagy is the straightforward mechanism by which a cell digests certain large internal structures and semi-permanent proteins in a continual cleanup process. The process may have evolved as a response to starvation, in which cells cannibalized some of their own parts in order to continue living. But over the eons it has become an essential tool used by cells to maintain their own health, resist infection and possibly even fight cancer.



Autophagy is particularly important in cells such as neurons, which tend to live a long time and thus need to be constantly renewed and refurbished. The process takes place in the cytoplasm, the jelly-like fluid that fills the cell outside the nucleus. As described in a 2008 article about autophagy in Scientific American, “the workings of the cytoplasm are so complex . . . that it is constantly becoming gummed up with the detritus of its ongoing operations. Autophagy is, in part, a cleanup process: the trash hauling that enables a cell whose cytoplasm is clotted with old bits of protein and other unwanted sludge to be cleaned out.” Problems with autophagy may contribute to neuronal damage in Alzheimer’s, Parkinson’s and other neurodegenerative diseases.

「オートファジーは、長生きしがちが故に常に更新と修復が必要なニューロン等の細胞において特に重要です。その工程は、核外の細胞を満たしているゼリー状液体である細胞質の中で行われています。2008年にScientific American誌でオートファジーについての記事に書かれているように、”細胞質のその機能は非常に複雑なため、継続的工程の堆積物で絶えず動きが悪くなっています。オートファジーは、部分的には、清掃工程で、細胞質が古いたんぱく質の破片や他の不要な沈殿物で詰まった細胞をきれいにするゴミ運搬作業です”、自己貪食に伴う問題が、アルツハイマー病、パーキンソン病、他の神経変性の病気において、神経損傷の一因になっている可能性があります。」


Understanding autophagy has taken decades. In the 1950s by Belgian scientist Christian de Duve had revealed a previously unknown structure within the cell that de Duve called a lysosome. He and others determined that the organelle contained many enzymes that would, under the right circumstances, tear apart proteins and even other organelles, allowing their constituent parts to be reused or ejected by the cells. De Duve was one of three people to win the Nobel Prize for this and other work in 1974.



And there things stood until the 1990s when Ohsumi decided to study the problem in yeast, which are often used in the lab to model the basic processes at work in the cells of higher organisms, including humans. For historical reasons, lysosomes in yeast are called vacuoles.


there things stood until ~で、~まで状況に変化なしみたいな意味合いになります。この場合は、thereがノーベル賞受賞時を指していて、ド・デューブの研究以降、彼の研究が1990年代まで支持され続けたみたいな感じです。70年代で既に研究に終止符が打たれたような感があったのかもしれませんが、やり残し感にチャンスを見い出した大隅教授の目の付けどころが、ある意味ノーベル賞級だったのかもしれません。

Many investigators at the time seemed to think that autophagy was important only in special circumstances, such as starvation. Vacuoles form in yeast when nutrients are scarce, which starts a process by which yeast develop spores that can spread presumably to more fertile territory. But Ohsumi viewed this lack of research focus as unique opportunity to have a research field almost entirely to himself. “I chose the transport of materials to the yeast vacuoles as my research project, because no one else was studying it,” Ohsumi said in an interview after winning the Inamori Foundation’s Kyoto Prize in 2012.



Today, scientists recognize that autophagy is fundamental to a cell’s continued good health and have even specialized in describing particular types of autophagy—such as the digestion and degradation of worn-out mitochondria (the powerhouse of the cell) and the endoplasmic reticulum, which assembles, folds and delivers proteins to the rest of the cell.