Smith Oliver, Palmer Sarah A, Clapham Alan J, Rose Pamela, Liu Yuan, Wang Jun, Allaby Robin G
School of Life Sciences, The University of Warwick, Coventry, United Kingdom.
The Austrian Archaeological Institute, Cairo Branch, Zamalek, Cairo, Egypt.
Mol Biol Evol. 2017 Oct 1;34(10):2555-2562. doi: 10.1093/molbev/msx175.
The recovery of ancient RNA from archeological material could enable the direct study of microevolutionary processes. Small RNAs are a rich source of information because their small size is compatible with biomolecular preservation, and their roles in gene regulation make them likely foci of evolutionary change. We present here the small RNA fraction from a sample of archeological barley generated using high-throughput sequencing that has previously been associated with localized adaptation to drought. Its microRNA profile is broadly similar to 19 globally distributed modern barley samples with the exception of three microRNAs (miRNA159, miRNA319, and miR396), all of which are known to have variable expression under stress conditions. We also found retrotransposon activity to be significantly reduced in the archeological barley compared with the controls, where one would expect the opposite under stress conditions. We suggest that the archeological barley's conflicting stress signals could be the result of long-term adaptation to its local environment.
从考古材料中恢复古代RNA能够直接研究微观进化过程。小RNA是丰富的信息来源，因为它们的小尺寸与生物分子保存相兼容，并且它们在基因调控中的作用使其可能成为进化变化的焦点。我们在此展示了通过高通量测序从一个考古大麦样本中获得的小RNA组分，该样本先前已与对干旱的局部适应相关联。其微小RNA谱与19个全球分布的现代大麦样本大致相似，但有三个微小RNA（miRNA159、miRNA319和miR396）除外，已知这三个微小RNA在应激条件下表达可变。我们还发现，与对照相比，考古大麦中的反转录转座子活性显著降低，而在应激条件下人们预期的情况则相反。我们认为，考古大麦相互矛盾的应激信号可能是长期适应其当地环境的结果。
