Cheetham-Wilkinson Izaak J, Sivalingam Bhavya, Flitton Chloe, Flottmann Franziska, Vehling Luisa, Drechsler Maik, Stojchevska Marija, Raimondi Andrea, Paululat Achim, Fröhlich Florian, Swan Laura E, Stagi Massimiliano
Department of Biochemistry Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK.
Division of Molecular Membrane Biology, Department of Biology/Chemistry, Osnabrück University, 49076 Osnabrück, Germany.
Sci Adv. 2025 Jan 3;11(1):eadr7325. doi: 10.1126/sciadv.adr7325.
Lysosomal pH dysregulation is a critical element of the pathophysiology of neurodegenerative diseases, cancers, and lysosomal storage disorders (LSDs). To study the role of lysosomes in pathophysiology, probes to analyze lysosomal size, positioning, and pH are indispensable tools. Here, we developed and characterized a ratiometric genetically encoded lysosomal pH probe, RpH-ILV, targeted to a subpopulation of lysosomal intraluminal vesicles. This subpopulation behaves similarly to the general population of LAMP1-positive vesicles in terms of pH response to pharmacological stresses. In addition, RpH-ILV, which is trafficked to the lysosome via a different cytosolic motif than our previous ratiometric sensor, RpH-LAMP1, is well tolerated by the model organism , exhibits minimal plasma membrane fluorescence, and reveals sensitivity to the lysosomal damaging agent LLOMe, adding a valuable tool to our repertoire of lysosomal pH sensors.
溶酶体pH失调是神经退行性疾病、癌症和溶酶体贮积症（LSDs）病理生理学的关键因素。为了研究溶酶体在病理生理学中的作用，用于分析溶酶体大小、定位和pH的探针是必不可少的工具。在这里，我们开发并表征了一种比率型基因编码的溶酶体pH探针RpH-ILV，它靶向溶酶体内腔囊泡的一个亚群。就对药理应激的pH反应而言，这个亚群的行为与LAMP1阳性囊泡的总体相似。此外，RpH-ILV通过与我们之前的比率型传感器RpH-LAMP1不同的胞质基序转运到溶酶体，模型生物对其耐受性良好，在质膜上的荧光最小，并显示出对溶酶体损伤剂亮抑酶肽（LLOMe）的敏感性，为我们的溶酶体pH传感器库增添了一个有价值的工具。
