普林斯顿大学生态与进化生物学系以及印第安纳大学生物系的研究者在Science杂志的在线版上发表关于垃圾DNA（junk DNA）的研究进展，A Functional Role for Transposases in a Large Eukaryotic Genome。
在基因组中存在有一部分不能表达蛋白的非编码序列，有很长的一段时间科学家们没有认为这些非编码的作用，因此，这些重复的DNA片段被冠以垃圾DNA的称号。随着时间的推移，科学家们对垃圾DNA的认识逐渐深入，慢慢地发现其实很多非编码DNA有着其独特的作用，它们在基因剪切等方面起重要的作用。
普林斯顿大学的青年女教授Laura Landweber的研究成果也证实了这一点。Laura Landweber研究小组发现Oxytricha在发育的过程中，基因组经历不断的剪接重排。在这些重排的过程中，转座子酶（transposases）起重要的作用。在转座子酶的作用下，转座子对基因组进行编辑，当完成发育完成后，转座子又被转座子酶清除掉。
这些都表明，原本认为是废物DNA的序列其实也有其存在的价值。垃圾DNA并不垃圾。(生物谷Bioon.com)
生物谷推荐原始出处：
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.
