普林斯頓大學(xué)生態(tài)與進化生物學(xué)系以及印第安納大學(xué)生物系的研究者在Science雜志的在線版上發(fā)表關(guān)于垃圾DNA（junk DNA）的研究進展,，A Functional Role for Transposases in a Large Eukaryotic Genome,。
在基因組中存在有一部分不能表達蛋白的非編碼序列，有很長的一段時間科學(xué)家們沒有認為這些非編碼的作用,，因此,，這些重復(fù)的DNA片段被冠以垃圾DNA的稱號。隨著時間的推移,，科學(xué)家們對垃圾DNA的認識逐漸深入，慢慢地發(fā)現(xiàn)其實很多非編碼DNA有著其獨特的作用,，它們在基因剪切等方面起重要的作用,。
普林斯頓大學(xué)的青年女教授Laura Landweber的研究成果也證實了這一點,。Laura Landweber研究小組發(fā)現(xiàn)Oxytricha在發(fā)育的過程中，基因組經(jīng)歷不斷的剪接重排,。在這些重排的過程中,，轉(zhuǎn)座子酶（transposases）起重要的作用。在轉(zhuǎn)座子酶的作用下,，轉(zhuǎn)座子對基因組進行編輯，當(dāng)完成發(fā)育完成后,，轉(zhuǎn)座子又被轉(zhuǎn)座子酶清除掉,。
這些都表明,，原本認為是廢物DNA的序列其實也有其存在的價值。垃圾DNA并不垃圾,。(生物谷Bioon.com)
生物谷推薦原始出處：
Science 15 May 2009:DOI: 10.1126/science.1170023
A Functional Role for Transposases in a Large Eukaryotic Genome
Mariusz Nowacki,1 Brian P. Higgins,1 Genevieve M. Maquilan,1 Estienne C. Swart,1 Thomas G. Doak,2 Laura F. Landweber1,*
Despite comprising much of the eukaryotic genome, few transposons are active, and they usually confer no benefit to the host. Through an exaggerated process of genome rearrangement, Oxytricha trifallax destroys 95% of its germline genome during development. This includes the elimination of all transposon DNA. We show that germline-limited transposase genes play key roles in this process of genome-wide DNA excision, which suggests that transposases function in large eukaryotic genomes containing thousands of active transposons. We show that transposase gene expression occurs during germline-soma differentiation and that silencing of transposase by RNA interference leads to abnormal DNA rearrangement in the offspring. This study suggests a new important role in Oxytricha for this large portion of genomic DNA that was previously thought of as junk.
1 Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA.
2 Department of Biology, Indiana University, Bloomington, IN 47405, USA.
