3000万年前逆转录病毒的传播史
文章来源:未知 文章作者:enread 发布时间:2016-03-09 05:35 字体: [ ]  进入论坛
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Researchers from Boston College, US, have revealed the global spread of an ancient group of retroviruses that affected1 about 28 of 50 modern mammals' ancestors some 15 to 30 million years ago. Retroviruses are abundant in nature and include human immunodeficiency viruses (HIV-1 and -2) and human T-cell leukemia viruses. The scientists' findings on a specific group of these viruses called ERV-Fc, to be published in the journal eLife, show that they affected a wide range of hosts, including species as diverse as carnivores, rodents2, and primates3
 
The distribution of ERV-Fc among these ancient mammals suggests the viruses spread to every continent except Antarctica and Australia, and that they jumped from one species to another more than 20 times.
 
The study also places the origins of ERV-Fc at least as far back as the beginning of the Oligocene epoch4, a period of dramatic global change marked partly by climatic cooling that led to the Ice Ages. Vast expanses of grasslands5 emerged around this time, along with large mammals as the world's predominate fauna6.
 
"Viruses have been with us for billions of years, and exist everywhere that life is found. They therefore have a significant impact on the ecology and evolution of all organisms, from bacteria to humans," says co-author Welkin Johnson, Professor of Biology at Boston College where his team carried out the research.
 
"Unfortunately, viruses do not leave fossils behind, meaning we know very little about how they originate and evolve. Over the course of millions of years, however, viral genetic7 sequences accumulate in the DNA8 genomes of living organisms, including humans, and can serve as molecular9 'fossils' for exploring the natural history of viruses and their hosts."  
 
Using such "fossil" remnants, the team sought to uncover the natural history of ERV-Fc. They were especially curious to know where and when these pathogens were found in the ancient world, which species they infected, and how they adapted to their mammalian hosts.


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1 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。
2 rodents 1ff5f0f12f2930e77fb620b1471a2124     
n.啮齿目动物( rodent的名词复数 )
参考例句:
  • Rodents carry diseases and are generally regarded as pests. 啮齿目动物传播疾病,常被当作害虫对待。 来自《简明英汉词典》
  • Some wild rodents in Africa also harbor the virus. 在非洲,有些野生啮齿动物也是储毒者。 来自辞典例句
3 primates 9536f12c27d026e37c108bd6fc53dbba     
primate的复数
参考例句:
  • Primates are alert, inquisitive animals. 灵长目动物是机灵、好奇的动物。
  • Consciousness or cerebration has been said to have emerged in the evolution of higher primates. 据说意识或思考在较高级灵长类的进化中已出现。
4 epoch riTzw     
n.(新)时代;历元
参考例句:
  • The epoch of revolution creates great figures.革命时代造就伟大的人物。
  • We're at the end of the historical epoch,and at the dawn of another.我们正处在一个历史时代的末期,另一个历史时代的开端。
5 grasslands 72179cad53224d2f605476ff67a1d94c     
n.草原,牧场( grassland的名词复数 )
参考例句:
  • Songs were heard ringing loud and clear over the grasslands. 草原上扬起清亮激越的歌声。 来自《现代汉英综合大词典》
  • Grasslands have been broken and planted to wheat. 草原已经开垦出来,种上了小麦。 来自《简明英汉词典》
6 fauna 9kExx     
n.(一个地区或时代的)所有动物,动物区系
参考例句:
  • This National Park is an area with unique fauna and flora.该国家公园区域内具有独特的动物种群和植物种群。
  • Fauna is a biological notion means all the animal life in a particular region or period. 动物群是一个生物学的概念,指的是一个特定时期或者地区的所有动物。
7 genetic PgIxp     
adj.遗传的,遗传学的
参考例句:
  • It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
  • Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。
8 DNA 4u3z1l     
(缩)deoxyribonucleic acid 脱氧核糖核酸
参考例句:
  • DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
  • Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。
9 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。
TAG标签: species viruses hosts
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