Proximity is a fundamental concept in chemistry and biology, referring to the convergence of molecules to facilitate new molecular interactions or reactions. Hybrid biopolymers like glycosylphosphatidylinositol (GPI)-anchored proteins, ubiquitinated proteins, glycosylated RNAs (glycoRNAs), and RNAylated proteins exemplify this by covalent bonding of moieties that are often orthogonally active. Hybrid molecules like glycoRNAs are localized to new physical spaces, generating new interfaces for biological functions. To fully investigate the compositional and spatial features of molecules like glycoRNAs, flexible genetic and chemical tools that encompass different encoding and targeting biopolymers are required. Here we discuss concepts of molecular proximity and explore newer proximity labeling technologies that facilitate applications in RNA biology, cell surface biology, and the interface therein with a particular focus on glycoRNA biology. We review the advantages and disadvantages of methods pertaining to cell surface RNA identification and provide insights into the vast opportunities for method development in this area.

中文翻译：

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研究细胞表面的工具：邻近性作为糖RNA生物学的中心概念


邻近性是化学和生物学中的一个基本概念，指的是分子的聚合以促进新的分子相互作用或反应。混合生物聚合物，如糖基磷脂酰肌醇 (GPI) 锚定蛋白、泛素化蛋白、糖基化 RNA (gluRNA) 和 RNA 化蛋白，通过通常具有正交活性的部分的共价键合来证明这一点。像糖RNA这样的混合分子被定位到新的物理空间，为生物功能产生新的界面。为了充分研究糖RNA等分子的组成和空间特征，需要包含不同编码和靶向生物聚合物的灵活的遗传和化学工具。在这里，我们讨论分子邻近的概念，并探索更新的邻近标记技术，这些技术促进了 RNA 生物学、细胞表面生物学及其界面的应用，特别关注糖 RNA 生物学。我们回顾了与细胞表面 RNA 鉴定相关的方法的优点和缺点，并深入了解了该领域方法开发的巨大机会。