{"doi":"10.1101/2025.10.06.680726","title":"hpGRISZ: a high-performance fluorescent biosensor for in vivo imaging of synaptic zinc dynamics","abstract":"Abstract Despite the crucial role of synaptic Zn 2+ in neurotransmission and neural processing, direct in vivo measurement of Zn 2+ transients has remained challenging due to the limited responsiveness of existing fluorescent indicators. Here we report hpGRISZ (high-performance green indicator for synaptic Zn 2+ ), an ultraresponsive turn-on green fluorescent biosensor engineered through iterative linker optimization, mutagenesis, and directed evolution. hpGRISZ exhibits exceptional brightness, thermostability, and a large fluorescence response (F/F 0 ≈ 25) with micromolar affinity suitable for detecting extracellular synaptic Zn 2+ release. We comprehensively characterized hpGRISZ in vitro, in mammalian cells, and in vivo. A membrane-anchored version of hpGRISZ traffics robustly to the cell surface under physiological conditions, where it retains strong responsiveness and supports wide-field, two-photon, and fiber photometry recordings in awake mice. These assays revealed synaptic Zn 2+ dynamics across distinct brain regions and neuronal circuits. Together, our findings establish hpGRISZ as a powerful tool for dissecting zinc signaling in neural circuits and as a prototype for next-generation genetically encoded biosensors for in vivo imaging.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2025,"id":577120,"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":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.949,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":485130,"name":"Manoj Kumar","orcid":"0000-0001-5139-1425","position":1,"is_corresponding":false},{"id":1486337,"name":"Raquel Correia","orcid":"0000-0002-5708-858X","position":2,"is_corresponding":false},{"id":960609,"name":"Shengjie Yang","orcid":"0000-0002-2629-9130","position":3,"is_corresponding":false},{"id":1486680,"name":"Wenyuan Huang","orcid":null,"position":4,"is_corresponding":false},{"id":1028332,"name":"Carina Soares‐Cunha","orcid":"0000-0001-9470-644X","position":5,"is_corresponding":false},{"id":1486338,"name":"Patrick A. Cody","orcid":"0000-0002-4618-1340","position":6,"is_corresponding":false},{"id":860721,"name":"Yiyu Zhang","orcid":"0000-0001-8636-2827","position":7,"is_corresponding":false},{"id":860720,"name":"Xiaodong Tian","orcid":"0000-0001-9590-9943","position":8,"is_corresponding":false},{"id":762222,"name":"Shengyu Zhao","orcid":"0000-0002-2501-8464","position":9,"is_corresponding":false},{"id":275972,"name":"Mikhail Drobizhev","orcid":"0000-0001-9072-1300","position":10,"is_corresponding":false},{"id":1486339,"name":"Ana João Rodrigues","orcid":"0000-0003-1968-7968","position":11,"is_corresponding":false},{"id":307830,"name":"Thanos Tzounopoulos","orcid":"0000-0003-4583-145X","position":12,"is_corresponding":false},{"id":336191,"name":"Hui‐wang Ai","orcid":"0000-0002-5664-3270","position":13,"is_corresponding":false},{"id":1486336,"name":"Hao Zhang","orcid":"0000-0003-0657-8957","position":0,"is_corresponding":true}],"reference_count":60,"raw_metadata":null,"created_at":"2026-07-19T02:58:04.622308Z","pmid":"41279334","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":[]}