科学家首次成功培育出灭绝动物的活体胚胎

sunsong7

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来自新南威尔士大学的科学家们报告称，他们已经成功培育出30年前灭绝的一种动物的活体胚胎。这项突破能够最终被用于复活其它已经灭绝的物种。保护生物学家迈克尔-马赫尼告诉《悉尼先驱晨报》道：“这项技术是第一次用于获取一个灭绝的物种。”, t) d+ _4 g* x( X0 R

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2 X1 _- @6 C! h科学家称，成功发育成蝌蚪也只是时间问题。" K9 ~$ z+ R8 N. f$ E  ?

1 g+ M/ L% U8 s3 O6 K这项试验使用了保存完好的胃育蛙的非活体遗传物质，这种青蛙在20世纪80年代中期已经灭绝。研究人员将DNA注入到一种类似青蛙物种的卵子中，这一过程与克隆绵羊多利的过程是不同的。而且在几天之后，胃育蛙的胚胎在30年后第一次获得了生命。新南威尔士大学的研究人员麦克-阿彻说道，最初蛙卵似乎并不活跃，但是随后突然有一个细胞分裂了，然后它不断的分裂。
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科学家称，尽管胚胎最终未能发育成一只蝌蚪，但是它只是时间问题。体细胞核转移技术最终会成功将这一物种或者其它的物种带回到可生育的成熟期。阿彻说道：“我们确实期待这种动物再一次活过来。”直到最近，复活灭绝动物的概念才摆脱科幻小说的范围，但是随着细胞移植技术的进步，它能够为那些不断走向灭亡的无数物种以及那些在历史中灭绝的物种带来一线希望。（过客/编译）2 U: `" f0 ~$ ~2 T" x( ?
Extinct frog hops back into the gene poolDateMarch 15, 2013http://www.smh.com.au/environment/animals/extinct-frog-hops-back-into-the-gene-pool-20130315-2g68x.html
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EXCLUSIVE  s/ q* [/ q; d/ ^; ~  ]
In what may be considered an early Easter miracle, an extinct species of native frog has begun its rise from the dead.. ?. ]9 ]7 f4 b
Australian scientists have grown embryos containing the revived DNA of the extinct gastric-brooding frog, the crucial first step in their attempt to bring a species back to life.
4 X1 l! T! W; h3 e, LThe team from the aptly named Lazarus project inserted the dead genetic material of the extinct amphibian into the donor eggs of another species of living frog, a process similar to the technique used to create the cloned sheep Dolly. The eggs continued to grow into three-day-old embryos, known as blastulas.5 {# c7 T# u2 b$ v$ I) e4 g' L
Extict since 1983: The bizarre gastric-brooding frog.
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! @+ X; y9 H1 u& L"This is the first time this technique has been achieved for an extinct species," said one of the project scientists, conservation biologist Michael Mahony.+ K/ t" h% Q) L3 _4 J6 G2 Y) P. [
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0 k( L/ g5 b7 i9 n. G7 _While many scientists have argued it would be impossible to bring a species back from the dead like in the film Jurassic Park, the Lazarus project's breakthrough suggested the revival of extinct species was no longer the realm of science fiction.5 J. J5 V: o& h
Over five years the team led by University of NSW palaeontologist Mike Archer painstakingly inserted DNA extracted from a frozen specimen of the bizarre gastric-brooding frog, which incubated its eggs in its stomach before giving birth through its mouth, into hundreds of donor eggs from a distant relative, the great barred frog, whose DNA had been deactivated by UV light.
% Y; z8 ^* F( [8 |- hFrozen for 40 years& u) s2 X; q8 [+ a# ?# p+ U% \& r
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In the beginning, the single cell eggs "just sat there", said Professor Archer. "But then, all of a sudden, one of the cells divided, and then it divided again, and again.4 N( F9 q" Z: b7 R4 t- b6 s# x( m+ q
"There were a lot of high fives around the laboratory at that point," said Professor Archer, who was to announce the team's achievement at the TEDxDeExtinction event in Washington on Friday.& N! v# _6 g/ u( Y
While the embryos had yet to develop into tadpoles, genetic tests revealed the dividing cells contained the DNA of the extinct frog.
6 _) l( Q. ~9 L( I2 Z; d" JThe egg donor frog.
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! r+ d3 c; R' G7 x2 v* L, Q7 i"We do expect to get this guy hopping again," Professor Archer said.
7 O& i# H' V/ F" I: PThe team has also demonstrated that the cloning technique, known as somatic nuclear cell transfer, could be used to conserve the genomes of other critically endangered species, particularly frogs, whose populations have plummeted around the world.
( ~5 f: u3 A8 z& L3 e"We haven't brought back the gastric-brooding frog yet but we've developed a tool that can stop other frogs going extinct," said Professor Mahony, from the University of Newcastle.
4 {7 c  N1 o  H8 P; i7 rDetermined to bring the species back to life: Professor Michael Archer. Photo: Marco Del Grande% [1 u: \6 ~- q0 u8 O, }

$ X; U. s! d4 C" J' M% qBut the team's success so far did not come easily.. r2 G+ s3 k2 ]: c
"It's not as if we're following a recipe," said Professor Archer.
* u( B. u5 q4 h0 gThe project would have remained a science fiction fantasy were it not for the foresight of Adelaide frog researcher, Mike Tyler, who froze a gastric-brooding frog specimen before it disappeared from the wild in 1979 and became extinct in 1983.
! A* q# g5 c% o9 g* C( V7 o6 O' d"It's a minor miracle that a university freezer hasn't been turned off in a power failure," Professor Archer said.
$ B% s- b/ Q* l3 ]The leader of the technical work, Monash University reproductive biologist Andrew French, said it was also amazing the team was able to extract viable DNA from the dead frog's cells.5 T1 t' P" w; e0 O7 Q4 W
The annual breeding cycle of the donor egg frog also meant the team had only a few weeks a year to conduct their experiments, Dr French said." p& W# B) J; M! e9 R  E- D' f
While the results are yet to be published, the group felt it was time to talk about their success.: l0 p& C6 k+ i" p
"We thought it was probably time to put the flag in the sand," said Professor Archer, who has previously directed attempts to revive the extinct Tasmanian tiger.
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ljs

1.这是一个重大的进步。一个新的起点、转折点。/ i% }9 }2 L0 b$ y( h# T/ W
2.将此技术应用到其他的灭绝生物上，绝对不是一片光明的。蛙属于两栖动物，它的受精卵的发育有很大的独特性，不具有代表性，这也是这个作者的切入点，谈不上突破点。甚至可以略带恶毒的说，这是作者的“投机取巧”。——70、80后是否记得小学课本上童第周？！蛙的受精卵人为切成2半，可以继续生长发育。) L$ d! A- @7 Q, S) g- w  t; v
3.此次尝试唯一的亮点就是培育出灭绝生物的胚胎，没有技术的创新，属于技术应用的拓展。培育出来的胚胎是否就是已经灭绝的胃育蛙，需要后面在形态、组织、遗传、DNA水平上评价。
' N% w* d7 b" q* `( c2 D7 j8 z/ T- e4.像干细胞输注一样，如果DNA输注稍有不成熟的地方——事实上也的确技术不成熟，培育出来的有可能是“杂交蛙”——胃育蛙和注入的卵子通过DNA杂交出来的杂交品种。对于本文预料的结果——培育出真正的胃育蛙的胚胎，我持谨慎、怀疑的态度。) p9 B1 p+ @/ O" i" x; s- B  H
5.因此凭借这个技术将其他的灭绝生物重生，未来的路会很漫长，也将非常曲折。“培育出灭绝生物”是生物界必然要面对的课题，但是仅仅通过DNA输注这条路是远远不够的。

aulenuyah

个人觉得这个多少也算是一种尝试，只不过希望能够见到一些哺乳动物或者鸟类的进展

santian538

恐龙的时代能否再现呢