{"doi":"10.1101/2020.11.04.368654","title":"A genetically encoded, pH-sensitive mTFP1 biosensor for probing lysosomal pH","abstract":"ABSTRACT Lysosomes are important sites for macromolecular degradation, defined by an acidic lumenal pH of ∼4.5. To better understand lysosomal pH, we designed a novel, genetically encoded, fluorescent protein (FP) based pH biosensor called FIRE-pHLy ( F luorescence Indicator RE porting pH in Ly sosomes). This biosensor was targeted to lysosomes with lysosomal-associated membrane protein 1 (LAMP1) and reported lumenal pH between 3.5 and 6.0 with monomeric teal fluorescent protein 1 (mTFP1), a bright cyan pH sensitive FP variant with a pKa of 4.3. Ratiometric quantification was enabled with cytosolically oriented mCherry using high-content quantitative imaging. We expressed FIRE-pHLy in several cellular models and quantified the alkalinizing response to bafilomycin A1, a specific V-ATPase inhibitor. In summary, we have engineered FIRE-pHLy, a specific, robust and versatile lysosomal pH biosensor that has broad applications for investigating pH dynamics in aging and lysosome-related diseases, as well as in lysosome-based drug discovery.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2020,"id":123239,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":4,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9487,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":247559,"name":"Anand Patwardhan","orcid":"0000-0002-3646-7978","position":1,"is_corresponding":false},{"id":566610,"name":"Kean-Hooi Ang","orcid":null,"position":2,"is_corresponding":false},{"id":566003,"name":"Austin L. Wang","orcid":"0000-0003-1860-2993","position":3,"is_corresponding":false},{"id":353566,"name":"Carolina Alquézar","orcid":"0000-0002-7452-3176","position":4,"is_corresponding":false},{"id":566611,"name":"Mackenzie Welch","orcid":null,"position":5,"is_corresponding":false},{"id":110074,"name":"Phi T. Nguyen","orcid":"0000-0001-5598-9213","position":6,"is_corresponding":false},{"id":283122,"name":"Michael Grabe","orcid":"0000-0003-3509-5997","position":7,"is_corresponding":false},{"id":227669,"name":"Anna V. Molofsky","orcid":"0000-0002-4709-2411","position":8,"is_corresponding":false},{"id":246284,"name":"Michelle R. Arkin","orcid":"0000-0002-9366-6770","position":9,"is_corresponding":false},{"id":353569,"name":"Aimee W. Kao","orcid":"0000-0002-7686-7968","position":10,"is_corresponding":false},{"id":566002,"name":"Marcus Y. Chin","orcid":"0000-0002-7037-1603","position":0,"is_corresponding":true}],"reference_count":90,"raw_metadata":null,"created_at":"2026-07-18T23:14:59.547352Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}