亨廷顿舞蹈病可能由蛋白质突变导致
文章来源:未知 文章作者:meng 发布时间:2010-04-12 03:29 字体: [ ]  进入论坛
(单词翻译:双击或拖选)

In a step towards a possible treatment for Huntington's disease, scientists at Albert Einstein College of Medicine of Yeshiva University have shown for the first time that the accumulation of a mutated(变化,突变) protein may explain damaging cellular1 behavior in Huntington's disease. Their research is described in the April 11 online edition of Nature Neuroscience. Huntington's disease, which afflicted2(折磨,使痛苦) the folksinger Woody Guthrie, is a fatal, inherited neurodegenerative(神经变性的) disorder4. While subtle personality changes and diminished(减退的) physical skills may occur early in the disease, it typically becomes noticeable during middle age. Later problems include dementia(痴呆) and chorea(舞蹈病) – jerky movements that are random5 and uncontrollable.

Huntington's disease results from a gene3 mutation6 that leads to a defective7 form of the huntingtin(变异亨廷顿蛋白) protein. The mutation is dominant8(支配的,统治的) , meaning that a child of an affected9 parent has a 50 percent chance of inheriting Huntington's. And since the defective protein is present in all of a person's cells, the disease causes problems in the brain and throughout the body.

"Studies have shown that Huntington's disease occurs in part because the mutated huntingtin protein accumulates within cells and is toxic10 to them," said Ana Maria Cuervo, M.D., Ph.D., professor of developmental and molecular11 biology, of anatomy12 and structural13 biology, and of medicine at Einstein and senior author of the Nature Neuroscience study. "In our investigation14 of how the accumulating huntingtin protein affects the functioning of cells, we found that it interferes15 with the cells' ability to digest and recycle their contents."

All cells rely on several different mechanisms17 to break down "old" proteins and other components18 and recycle them. Collectively known as autophagy(自我吞噬) (literally, "self-eating"), these processes keep cells clean and uncluttered(整洁的,整齐的) and provide them with replacement19 parts that will function better.

Dr. Cuervo and her team had previously20 shown that a glitch21(小故障,失灵) in autophagy may trigger Parkinson's disease by allowing a toxic protein to accumulate. She suspected that something similar was going on in Huntington's disease. After studying two mouse models of Huntington's disease as well as lymphoblasts (white cells) from people with the disease, she and her team found that the mutated huntingtin protein was sabotaging22(妨害,破坏) the cell's garbage-collecting efforts.

One mechanism16 for cleaning up cells involves forming a membrane23 around the protein or other cellular structure requiring removal. These "garbage bags" (more formally known as autophagosomes) then travel to enzyme-filled sacs known as lysosomes(溶酶体) that fuse with(融合,联合) the bags and digest their cargo24. But the clean-up efforts go awry25 in Huntington's disease.

Dr. Cuervo and her team found that the defective huntingtin proteins stick to the inner layer of autophagosomes, preventing them from gathering26 garbage. The result: Autophagosomes arrive empty at the lysosomes; and cellular components that should be recycled instead accumulate, causing toxicity27 that probably contributes to cell death.

This finding, Dr. Cuervo noted28, shows that activating29 the lysosomes of cells – one of the proposed treatments for Huntington's disease – won't do any good.

"It doesn't matter how active your lysosomes are if they're not going to receive any cellular components to digest," she said. "Instead, we should focus on treatments to help autophagosomes recognize intracellular(细胞内的) garbage, perhaps by minimizing their contact with the defective huntingtin protein. By enhancing the clearance30 of cellular debris31, we may be able to keep Huntington's patients free of symptoms(症状) for a longer time."



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1 cellular aU1yo     
adj.移动的;细胞的,由细胞组成的
参考例句:
  • She has a cellular telephone in her car.她的汽车里有一部无线通讯电话机。
  • Many people use cellular materials as sensitive elements in hygrometers.很多人用蜂窝状的材料作为测量温度的传感元件。
2 afflicted aaf4adfe86f9ab55b4275dae2a2e305a     
使受痛苦,折磨( afflict的过去式和过去分词 )
参考例句:
  • About 40% of the country's population is afflicted with the disease. 全国40%左右的人口患有这种疾病。
  • A terrible restlessness that was like to hunger afflicted Martin Eden. 一阵可怕的、跟饥饿差不多的不安情绪折磨着马丁·伊登。
3 gene WgKxx     
n.遗传因子,基因
参考例句:
  • A single gene may have many effects.单一基因可能具有很多种效应。
  • The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。
4 disorder Et1x4     
n.紊乱,混乱;骚动,骚乱;疾病,失调
参考例句:
  • When returning back,he discovered the room to be in disorder.回家后,他发现屋子里乱七八糟。
  • It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。
5 random HT9xd     
adj.随机的;任意的;n.偶然的(或随便的)行动
参考例句:
  • The list is arranged in a random order.名单排列不分先后。
  • On random inspection the meat was found to be bad.经抽查,发现肉变质了。
6 mutation t1PyM     
n.变化,变异,转变
参考例句:
  • People who have this mutation need less sleep than others.有这种突变的人需要的睡眠比其他人少。
  • So far the discussion has centered entirely around mutation in the strict sense.到目前为止,严格来讲,讨论完全集中于围绕突变问题上。
7 defective qnLzZ     
adj.有毛病的,有问题的,有瑕疵的
参考例句:
  • The firm had received bad publicity over a defective product. 该公司因为一件次品而受到媒体攻击。
  • If the goods prove defective, the customer has the right to compensation. 如果货品证明有缺陷, 顾客有权索赔。
8 dominant usAxG     
adj.支配的,统治的;占优势的;显性的;n.主因,要素,主要的人(或物);显性基因
参考例句:
  • The British were formerly dominant in India.英国人从前统治印度。
  • She was a dominant figure in the French film industry.她在法国电影界是个举足轻重的人物。
9 affected TzUzg0     
adj.不自然的,假装的
参考例句:
  • She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
  • His manners are affected.他的态度不自然。
10 toxic inSwc     
adj.有毒的,因中毒引起的
参考例句:
  • The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
  • There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。
11 molecular mE9xh     
adj.分子的;克分子的
参考例句:
  • The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
  • For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时,分子的碰撞就停止了。
12 anatomy Cwgzh     
n.解剖学,解剖;功能,结构,组织
参考例句:
  • He found out a great deal about the anatomy of animals.在动物解剖学方面,他有过许多发现。
  • The hurricane's anatomy was powerful and complex.对飓风的剖析是一项庞大而复杂的工作。
13 structural itXw5     
adj.构造的,组织的,建筑(用)的
参考例句:
  • The storm caused no structural damage.风暴没有造成建筑结构方面的破坏。
  • The North American continent is made up of three great structural entities.北美大陆是由三个构造单元组成的。
14 investigation MRKzq     
n.调查,调查研究
参考例句:
  • In an investigation,a new fact became known, which told against him.在调查中新发现了一件对他不利的事实。
  • He drew the conclusion by building on his own investigation.他根据自己的调查研究作出结论。
15 interferes ab8163b252fe52454ada963fa857f890     
vi. 妨碍,冲突,干涉
参考例句:
  • The noise interferes with my work. 这噪音妨碍我的工作。
  • That interferes with my plan. 那干扰了我的计划。
16 mechanism zCWxr     
n.机械装置;机构,结构
参考例句:
  • The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
  • The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。
17 mechanisms d0db71d70348ef1c49f05f59097917b8     
n.机械( mechanism的名词复数 );机械装置;[生物学] 机制;机械作用
参考例句:
  • The research will provide direct insight into molecular mechanisms. 这项研究将使人能够直接地了解分子的机理。 来自《简明英汉词典》
  • He explained how the two mechanisms worked. 他解释这两台机械装置是如何工作的。 来自《简明英汉词典》
18 components 4725dcf446a342f1473a8228e42dfa48     
(机器、设备等的)构成要素,零件,成分; 成分( component的名词复数 ); [物理化学]组分; [数学]分量; (混合物的)组成部分
参考例句:
  • the components of a machine 机器部件
  • Our chemistry teacher often reduces a compound to its components in lab. 在实验室中化学老师常把化合物分解为各种成分。
19 replacement UVxxM     
n.取代,替换,交换;替代品,代用品
参考例句:
  • We are hard put to find a replacement for our assistant.我们很难找到一个人来代替我们的助手。
  • They put all the students through the replacement examination.他们让所有的学生参加分班考试。
20 previously bkzzzC     
adv.以前,先前(地)
参考例句:
  • The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
  • Let me digress for a moment and explain what had happened previously.让我岔开一会儿,解释原先发生了什么。
21 glitch Pejzq     
n.干扰;误操作,小故障
参考例句:
  • There is a glitch in the computer program somewhere.这个计算机程序中的某个部分有点小问题。
  • It could just be a random glitch that can be solved by restarting the machine.可能只是一个小故障,重新启动主机就能解决了。
22 sabotaging ba20b6ee606869e83e5a042beefced7e     
阴谋破坏(某事物)( sabotage的现在分词 )
参考例句:
  • Mr Smith fiercely denied any question of sabotaging the talks. 史密斯先生坚决拒绝任何企图阻挠谈话的提问。
  • Failed in sabotaging APEC summit in Sydney of Australia. 澳大利亚悉尼APEC会议遭遇惨败。
23 membrane H7ez8     
n.薄膜,膜皮,羊皮纸
参考例句:
  • A vibrating membrane in the ear helps to convey sounds to the brain.耳膜的振动帮助声音传送到大脑。
  • A plastic membrane serves as selective diffusion barrier.一层塑料薄膜起着选择性渗透屏障的作用。
24 cargo 6TcyG     
n.(一只船或一架飞机运载的)货物
参考例句:
  • The ship has a cargo of about 200 ton.这条船大约有200吨的货物。
  • A lot of people discharged the cargo from a ship.许多人从船上卸下货物。
25 awry Mu0ze     
adj.扭曲的,错的
参考例句:
  • She was in a fury over a plan that had gone awry. 计划出了问题,她很愤怒。
  • Something has gone awry in our plans.我们的计划出差错了。
26 gathering ChmxZ     
n.集会,聚会,聚集
参考例句:
  • He called on Mr. White to speak at the gathering.他请怀特先生在集会上讲话。
  • He is on the wing gathering material for his novels.他正忙于为他的小说收集资料。
27 toxicity InYwc     
n.毒性,毒力
参考例句:
  • The hoarse grunt or squeal is characteristic of toxicity.嘶哑的哼声和叫声是中毒的特征。
  • Dieldrin is related to aldrin,and its toxicity to earthworms is similar.狄氏剂与艾氏剂有关,对蚯蚓的毒性是相似的。
28 noted 5n4zXc     
adj.著名的,知名的
参考例句:
  • The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
  • Jim is noted for arriving late for work.吉姆上班迟到出了名。
29 activating 948eea612456562bf255d3a9c59c40a3     
活动的,活性的
参考例句:
  • "I didn't say we'd got to stop activating the masses! “我并没说就此不发动! 来自子夜部分
  • Presumably both the very small size and activating influence of fluorine atoms contribute to this exception. 这大概是由于氟原子半径小和活性高这两个原因的影响,氟原子对这种例外做出了贡献。
30 clearance swFzGa     
n.净空;许可(证);清算;清除,清理
参考例句:
  • There was a clearance of only ten centimetres between the two walls.两堵墙之间只有十厘米的空隙。
  • The ship sailed as soon as it got clearance. 那艘船一办好离港手续立刻启航了。
31 debris debris     
n.瓦砾堆,废墟,碎片
参考例句:
  • After the bombing there was a lot of debris everywhere.轰炸之后到处瓦砾成堆。
  • Bacteria sticks to food debris in the teeth,causing decay.细菌附着在牙缝中的食物残渣上,导致蛀牙。
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