School of Chemistry and Biochemistry, National Centre of Competence in Research (NCCR) Chemical Biology, University of Geneva, Geneva, Switzerland.
Angew Chem Int Ed Engl. 2021 May 25;60(22):12258-12263. doi: 10.1002/anie.202016105. Epub 2021 Apr 26.
Fluorescent flipper probes have been introduced recently to image membrane tension in live cells, and strategies to target these probes to specific membranes are emerging. In this context, early endosome (EE) targeting without the use of protein engineering is especially appealing because it translates into a fascinating transport problem. Weakly basic probes, commonly used to track the inside of acidic late endosomes and lysosomes, are poorly retained in EE because they are sufficiently neutralized in weakly acidic EE, thus able to diffuse out. Here, we disclose a rational strategy to target EE using a substituted benzylamine with a higher pK value as a head group of the flipper probe. The resulting EE flippers are validated for preserved mechanosensitivity, ready for use in biology, particularly to elucidate the mechanics of endocytosis.
荧光翻转探针最近被引入用于对活细胞中的膜张力进行成像，并且将这些探针靶向特定膜的策略也在不断涌现。在这种情况下，不使用蛋白质工程而靶向早期内体（EE）尤其吸引人，因为这转化为一个引人入胜的运输问题。弱碱性探针通常用于跟踪酸性晚期内体和溶酶体的内部，但由于它们在弱酸性 EE 中被充分中和，因此能够扩散出来，因此在 EE 中保留较差。在这里，我们披露了一种使用具有更高 pK 值的取代苄胺作为翻转探针的头基来靶向 EE 的合理策略。所得的 EE 翻转探针经过验证具有保留的机械敏感性，可随时用于生物学研究，特别是用于阐明胞吞作用的力学。
