一个由香港大学李笑宇、重庆大学李亦舟和海军军医大学曹岩等组成的合作小组，近日开发出一种针对活细胞上的内源性膜蛋白开展DNA编码文库筛选的方法。 该研究于2020年12月21日发表于国际一流学术期刊《自然·化学》杂志上。

在该文中，研究人员报道了一种用DNA标签特异性标记膜蛋白的方法，从而可在不进行过表达或其他基因操作的前提下，针对活细胞上的内源性膜蛋白开展靶标特异性的DNA编码文库筛选。针对活细胞上的叶酸受体、碳酸酐酶12和表皮细胞生长因子，研究人员从一个含3042万化合物的DNA编码文库进行筛选，找到并验证了一系列这些靶标的新配体，从而展示了该方法的普适性和高效性。由于膜蛋白在治疗中的巨大价值，以及其无法适用于传统的高通量筛选策略，通过驾驭DNA编码文库的巨大潜力，该方法有望大大加速基于膜蛋白的药物发现过程。

据了解，细胞表面的膜蛋白具有多种生物学功能。然而，发现膜蛋白的配体非常具有挑战性，因为通常需要天然的细胞环境来维持膜蛋白的结构和功能。DNA编码化学文库（DEL）已成为一种强大的配体发现技术，但主要限于纯化后的蛋白质。

附：英文原文

Title: Selection of DNA-encoded chemical libraries against endogenous membrane proteins on live cells

Author: Yiran Huang, Ling Meng, Qigui Nie, Yu Zhou, Langdong Chen, Shilian Yang, Yi Man Eva Fung, Xiaomeng Li, Cen Huang, Yan Cao, Yizhou Li, Xiaoyu Li

Issue&Volume: 2020-12-21

Abstract: Membrane proteins on the cell surface perform a myriad of biological functions; however, ligand discovery for membrane proteins is highly challenging, because a natural cellular environment is often necessary to maintain protein structure and function. DNA-encoded chemical libraries (DELs) have emerged as a powerful technology for ligand discovery, but they are mainly limited to purified proteins. Here we report a method that can specifically label membrane proteins with a DNA tag, and thereby enable target-specific DEL selections against endogenous membrane proteins on live cells without overexpression or any other genetic manipulation. We demonstrate the generality and performance of this method by screening a 30.42-million-compound DEL against the folate receptor, carbonic anhydrase 12 and the epidermal growth factor receptor on live cells, and identify and validate a series of novel ligands for these targets. Given the high therapeutic significance of membrane proteins and their intractability to traditional high-throughput screening approaches, this method has the potential to facilitate membrane-protein-based drug discovery by harnessing the power of DEL.

DOI: 10.1038/s41557-020-00605-x

Source: https://www.nature.com/articles/s41557-020-00605-x