Department of Computer Science and Technology, Jilin University, Changchun, Jilin, China.
Department of Electrical Engineering and Computer Science, and Christopher S Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America.
PLoS One. 2018 Jun 27;13(6):e0187519. doi: 10.1371/journal.pone.0187519. eCollection 2018.
In recent years, an increasing number of studies have reported the presence of plant miRNAs in human samples, which resulted in a hypothesis asserting the existence of plant-derived exogenous microRNA (xenomiR). However, this hypothesis is not widely accepted in the scientific community due to possible sample contamination and the small sample size with lack of rigorous statistical analysis. This study provides a systematic statistical test that can validate (or invalidate) the plant-derived xenomiR hypothesis by analyzing 388 small RNA sequencing data from human samples in 11 types of body fluids/tissues. A total of 166 types of plant miRNAs were found in at least one human sample, of which 14 plant miRNAs represented more than 80% of the total plant miRNAs abundance in human samples. Plant miRNA profiles were characterized to be tissue-specific in different human samples. Meanwhile, the plant miRNAs identified from microbiome have an insignificant abundance compared to those from humans, while plant miRNA profiles in human samples were significantly different from those in plants, suggesting that sample contamination is an unlikely reason for all the plant miRNAs detected in human samples. This study also provides a set of testable synthetic miRNAs with isotopes that can be detected in situ after being fed to animals.
近年来，越来越多的研究报告称在人类样本中存在植物 miRNAs，这导致了一个假设，即存在植物源性外源性 microRNA（xenomiR）。然而，由于可能存在样本污染以及缺乏严格的统计分析的小样本量，该假设在科学界并未得到广泛认可。本研究通过分析来自 11 种体液/组织的 388 个人类样本的小 RNA 测序数据，提供了一种系统的统计检验方法，可以通过分析来自 11 种体液/组织的 388 个人类样本的小 RNA 测序数据来验证（或否定）植物源性 xenomiR 假说。在至少一个人类样本中发现了 166 种植物 miRNAs，其中 14 种植物 miRNAs 代表了人类样本中总植物 miRNAs 丰度的 80%以上。植物 miRNA 图谱在不同的人类样本中表现出组织特异性。同时，与人类相比，从微生物组中鉴定出的植物 miRNA 丰度较低，而人类样本中的植物 miRNA 图谱与植物有显著差异，表明样本污染不太可能是所有在人类样本中检测到的植物 miRNAs 的原因。本研究还提供了一组经过同位素标记的可测试合成 miRNA，这些 miRNA 可以在动物喂食后进行原位检测。
