《哈利·波特》系列影片里的腮囊草看起来有一天会变成现实。科学家发现,通过把我们的DNA与这种海藻的结合在一起,或许有一天人类就能像鱼儿一样在水下呼吸。
他们研究蝾螈时发现,产生氧气的海藻可与这种动物的卵紧密结合在一起,以致现在二者已经无法分开。他们希望通过对这一机制进行更加深入的研究,有一天能把这种方法应用到人类身上,这样我们就能像《哈利·波特与火焰杯》里的哈利一样在水里自由遨游,不用担心会窒息而亡。在电影里,哈利吞下这种黏糊糊的植物后,脖子两边长出了腮,能像鱼儿一样在水里游来游去。
然而这项最新研究打算把我们的DNA与腮囊草的DNA结合在一起,让我们变得更像海藻,这种植物即使置身海底,仍能释放出氧气。加拿大哈利法克斯达尔豪斯大学的研究人员发现,自从人类诞生以来,我们的DNA吸收了数百种病毒。他们把这一理论应用到蝾螈身上,因为海藻经常会进入到它们的胚胎里,从某种意义上来说,一些蝾螈已经变成了半植物体。
这一发现首次证明了植物和脊椎动物之间存在的共生现象。科学家表示,或许有一天生物工程师可以把藻类当作其他生物体的氧气来源,其中包括人类。要想实现这种巨大跳跃,我们还需要进行大量试验,不过人类是像蝾螈一样的脊椎动物,因此这个目标很有可能会变成现实。
首席研究人员赖安·肯尼博士说:“卵囊里的海藻能为蝾螈的胚胎提供氧气,海藻从胚胎产生的废物里获取营养,胚胎里含有的大量氮正是这种植物需要的。我们还在成年蝾螈的生殖器里发现海藻的DNA,似乎这是可以遗传的。我们称这一现象为‘垂直传递’,与之结合的海藻可能是从外界吸收进来的。”该研究成果发表在《美国国家科学院院刊》上。(生物谷Bioon.com)
生物谷推荐原文出处:
PNAS doi: 10.1073/pnas.1018259108
Intracellular invasion of green algae in a salamander host
Ryan Kerneya,1, Eunsoo Kimb, Roger P. Hangarterc, Aaron A. Heissa, Cory D. Bishopd, and Brian K. Halla
The association between embryos of the spotted salamander (Ambystoma maculatum) and green algae (“Oophila amblystomatis” Lamber ex Printz) has been considered an ectosymbiotic mutualism. We show here, however, that this symbiosis is more intimate than previously reported. A combination of imaging and algal 18S rDNA amplification reveals algal invasion of embryonic salamander tissues and cells during development. Algal cells are detectable from embryonic and larval Stages 26–44 through chlorophyll autofluorescence and algal 18S rDNA amplification. Algal cell ultrastructure indicates both degradation and putative encystment during the process of tissue and cellular invasion. Fewer algal cells were detected in later-stage larvae through FISH, suggesting that the decline in autofluorescent cells is primarily due to algal cell death within the host. However, early embryonic egg capsules also contained encysted algal cells on the inner capsule wall, and algal 18S rDNA was amplified from adult reproductive tracts, consistent with oviductal transmission of algae from one salamander generation to the next. The invasion of algae into salamander host tissues and cells represents a unique association between a vertebrate and a eukaryotic alga, with implications for research into cell–cell recognition, possible exchange of metabolites or DNA, and potential congruence between host and symbiont population structures.