Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.
Department of Neuroscience, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia.
Methods Mol Biol. 2021;2298:31-52. doi: 10.1007/978-1-0716-1374-0_3.
RNA modifications play pivotal roles in the RNA life cycle and RNA fate, and are now appreciated as a major posttranscriptional regulatory layer in the cell. In the last few years, direct RNA nanopore sequencing (dRNA-seq) has emerged as a promising technology that can provide single-molecule resolution maps of RNA modifications in their native RNA context. While native RNA can be successfully sequenced using this technology, the detection of RNA modifications is still challenging. Here, we provide an upgraded version of EpiNano (version 1.2), an algorithm to predict mA RNA modifications from dRNA-seq datasets. The latest version of EpiNano contains models for predicting mA RNA modifications in dRNA-seq data that has been base-called with Guppy. Moreover, it can now train models with features extracted from both base-called dRNA-seq FASTQ data and raw FAST5 nanopore outputs. Finally, we describe how EpiNano can be used in stand-alone mode to extract base-calling "error" features and current intensity information from dRNA-seq datasets. In this chapter, we provide step-by-step instructions on how to produce in vitro transcribed constructs to train EpiNano, as well as detailed information on how to use EpiNano to train, test, and predict mA RNA modifications in dRNA-seq data.
RNA 修饰在 RNA 生命周期和 RNA 命运中发挥着关键作用,现在被认为是细胞中主要的转录后调控层。在过去的几年中,直接 RNA 纳米孔测序(dRNA-seq)已经成为一种很有前途的技术,可以提供 RNA 修饰在其天然 RNA 环境中的单分子分辨率图谱。虽然可以使用这项技术成功地对天然 RNA 进行测序,但 RNA 修饰的检测仍然具有挑战性。在这里,我们提供了 EpiNano(版本 1.2)的升级版本,这是一种从 dRNA-seq 数据集预测 mA RNA 修饰的算法。EpiNano 的最新版本包含了用于预测 dRNA-seq 数据中 mA RNA 修饰的模型,这些数据已经使用 Guppy 进行了碱基调用。此外,它现在可以使用从碱基调用的 dRNA-seq FASTQ 数据和原始 FAST5 纳米孔输出中提取的特征来训练模型。最后,我们描述了如何在独立模式下使用 EpiNano 从 dRNA-seq 数据集中提取碱基调用“错误”特征和当前强度信息。在本章中,我们提供了分步说明,介绍如何生成体外转录构建体来训练 EpiNano,以及如何使用 EpiNano 训练、测试和预测 dRNA-seq 数据中的 mA RNA 修饰的详细信息。