小柯机器人

美国莫格里奇研究所Joshua J. Coon和德国马克斯·普朗克生物化学研究所Jürgen Cox共同合作，近期取得重要研究进展。他们通过利用深度蛋白质组测序实现对人类蛋白变体和异构体进行整体检测。相关论文于2023年3月23日在线发表于《自然—生物技术》杂志上。

据介绍，一个普通的鸟枪法蛋白质组学实验从单个样本中检测到大约10000种人类蛋白质。然而，单个蛋白质通常通过代表其总氨基酸的一小部分的肽序列来鉴定。因此，一个普通的鸟枪法实验无法区分不同的蛋白质变体和异构体。因此，人们需要更深入的蛋白质组测序方法才能在整体范围内发现蛋白质异构体。

使用六种不同的人类细胞系、六种蛋白酶、深度分级和三种串联质谱裂解方法，研究人员从17717个蛋白质组中鉴定了一百万种独特的肽，其中位序列覆盖率约为80%。与RNA表达数据的直接比较为大多数非同义变体的翻译提供了证据。研究人员还假设，未被发现的变异可能是由突变诱导的蛋白质不稳定性。研究人员进一步观察到代表组成型和选择性剪接事件的外显子-外显子连接肽的可比检测率。

总之，这一数据集代表了一种用于发现蛋白质组的资源，并提供了直接证据表明大多数保留框架的选择性剪接异构体都已翻译。

附：英文原文

Title: Global detection of human variants and isoforms by deep proteome sequencing

Author: Sinitcyn, Pavel, Richards, Alicia L., Weatheritt, Robert J., Brademan, Dain R., Marx, Harald, Shishkova, Evgenia, Meyer, Jesse G., Hebert, Alexander S., Westphall, Michael S., Blencowe, Benjamin J., Cox, Jrgen, Coon, Joshua J.

Issue&Volume: 2023-03-23

Abstract: An average shotgun proteomics experiment detects approximately 10,000 human proteins from a single sample. However, individual proteins are typically identified by peptide sequences representing a small fraction of their total amino acids. Hence, an average shotgun experiment fails to distinguish different protein variants and isoforms. Deeper proteome sequencing is therefore required for the global discovery of protein isoforms. Using six different human cell lines, six proteases, deep fractionation and three tandem mass spectrometry fragmentation methods, we identify a million unique peptides from 17,717 protein groups, with a median sequence coverage of approximately 80%. Direct comparison with RNA expression data provides evidence for the translation of most nonsynonymous variants. We have also hypothesized that undetected variants likely arise from mutation-induced protein instability. We further observe comparable detection rates for exon–exon junction peptides representing constitutive and alternative splicing events. Our dataset represents a resource for proteoform discovery and provides direct evidence that most frame-preserving alternatively spliced isoforms are translated.

DOI: 10.1038/s41587-023-01714-x

Source: https://www.nature.com/articles/s41587-023-01714-x

Nature Biotechnology：《自然—生物技术》，创刊于1996年。隶属于施普林格·自然出版集团，最新IF：68.164
官方网址：https://www.nature.com/nbt/
投稿链接：https://mts-nbt.nature.com/cgi-bin/main.plex