Neme Rafik, Amador Cristina, Yildirim Burcin, McConnell Ellen, Tautz Diethard
Max-Planck Institute for Evolutionary Biology, August-Thienemannstrasse 2, 24306 Plön, Germany.
Nat Ecol Evol. 2017 Jun;1(6):0217. doi: 10.1038/s41559-017-0127. Epub 2017 Apr 24.
It is generally assumed that new genes arise through duplication and/or recombination of existing genes. The probability that a new functional gene could arise out of random non-coding DNA is so far considered to be negligible, since it seems unlikely that such a RNA or protein sequence could have an initial function that influences the fitness of an organism. We have here tested this question systematically, by expressing clones with random sequences in and subjecting them to competitive growth. Contrary to expectations, we find that random sequences with bioactivity are not rare. In our experiments we find that up to 25% of the evaluated clones enhance the growth rate of their cells and up to 52% inhibit growth. Testing of individual clones in competition assays confirms their activity and provides an indication that their activity could be exerted either by the transcribed RNA or the translated peptide. This suggests that transcribed and translated random parts of the genome could indeed have a high potential to become functional. The results also suggest that random sequences may become an effective new source of molecules for studying cellular functions, as well as for pharmacological activity screening.
一般认为新基因是通过现有基因的复制和/或重组产生的。到目前为止，随机非编码DNA产生新功能基因的概率被认为可以忽略不计，因为这样的RNA或蛋白质序列似乎不太可能具有影响生物体适应性的初始功能。我们在这里通过在[具体环境]中表达具有随机序列的克隆并使其经历竞争性生长，系统地测试了这个问题。与预期相反，我们发现具有生物活性的随机序列并不罕见。在我们的实验中，我们发现高达25%的评估克隆提高了其细胞的生长速率，高达52%的克隆抑制生长。在竞争试验中对单个克隆的测试证实了它们的活性，并表明它们的活性可能由转录的RNA或翻译的肽发挥。这表明基因组转录和翻译的随机部分确实很有可能成为功能性的。结果还表明，随机序列可能成为研究细胞功能以及进行药理活性筛选的有效新分子来源。
