The unraveling of the cellular effects of anion transporters is key to their potential development as apoptosis-inducing or autophagy-disrupting therapeutics. Here, we conducted a systematic study of the cellular responses to the anion transporter prodigiosin by using a pH on/off responsive near-infrared (NIR)-fluorescent probe in HeLa and LAMP1-GFP-transfected HeLa cell lines. The sequence of localized and global cellular acidity changes and the resulting outcomes induced by the anion transporter were visualized with high temporal and spatial resolution. The results show that prodigiosin causes the pH within the lysosomal lumen to rise, after which a non-organelle-specific increase in acidity of the cytosol takes place, which prompts cells to undergo apoptosis. This was confirmed by the quantification of NIR-emissive lysosomes, the intra-cellular fluorescence intensity, and fluorescence volume over time. This NIR probe overcame the limitations of acridine orange, which to date have severely restricted researchers in this field.

揭示阴离子转运蛋白的细胞作用是其作为凋亡诱导或自噬干扰治疗剂的潜在发展的关键。在这里，我们通过在HeLa和LAMP1-GFP转染的HeLa细胞系中使用pH开/关响应近红外（NIR）荧光探针对阴离子转运蛋白prodigiosin的细胞应答进行了系统的研究。局部和全局细胞酸度变化的序列以及由阴离子转运蛋白诱导的最终结果以高时空分辨率可视化。结果表明，地高辛配酶导致溶酶体腔内的pH升高，此后，细胞质的酸度发生了非细胞器特异性的增加，从而促使细胞发生凋亡。近红外发射溶酶体的定量证实了这一点，细胞内荧光强度和荧光量随时间的变化。这种NIR探针克服了a啶橙的局限性，迄今为止，limitations啶橙已严重限制了该领域的研究人员。