{"doi":"10.1101/2020.11.07.355651","title":"Chemoreceptor Co-Expression in <i>Drosophila</i> Olfactory Neurons","abstract":"Abstract Drosophila melanogaster olfactory neurons have long been thought to express only one chemosensory receptor gene family. There are two main olfactory receptor gene families in Drosophila , the Odorant Receptors (ORs) and the Ionotropic Receptors (IRs). The dozens of odorant binding receptors in each family require at least one co-receptor gene in order to function: Orco for ORs, and Ir25a , Ir8a , and Ir76b for IRs. Using a new genetic knock-in strategy, we targeted the four co-receptors representing the main chemosensory families in Drosophila ( Orco, Ir8a, Ir76b, Ir25a ). Co-receptor knock-in expression patterns were verified as accurate representations of endogenous expression. We find extensive overlap in expression among the different co-receptors. As defined by innervation into antennal lobe glomeruli, Ir25a is broadly expressed in 88% of all olfactory sensory neuron classes and is co-expressed in 82% of Orco+ neuron classes, including all neuron classes in the maxillary palp. Orco , Ir8a , and Ir76b expression patterns are also more expansive than previously assumed. Single sensillum recordings from Orco-expressing Ir25a mutant antennal and palpal neurons identify changes in olfactory responses. These results suggest co-expression of chemosensory receptors is common in olfactory neurons. Together, our data present the first comprehensive map of chemosensory co-receptor expression and reveal their unexpected widespread co-expression in the fly olfactory system.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2020,"id":119106,"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":28,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9441,"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":553454,"name":"Chun‐Chieh Lin","orcid":"0000-0001-9679-4287","position":1,"is_corresponding":false},{"id":553455,"name":"Alina Vulpe","orcid":"0000-0001-5385-3072","position":2,"is_corresponding":false},{"id":306024,"name":"Ali Afify","orcid":"0000-0002-6954-5776","position":3,"is_corresponding":false},{"id":553456,"name":"Sydney Ballou","orcid":"0000-0002-3053-1115","position":4,"is_corresponding":false},{"id":64648,"name":"Maria Brbić","orcid":"0000-0002-1120-1778","position":5,"is_corresponding":false},{"id":228484,"name":"Philipp Schlegel","orcid":"0000-0002-5633-1314","position":6,"is_corresponding":false},{"id":228495,"name":"Gregory S.X.E. Jefferis","orcid":"0000-0002-0587-9355","position":7,"is_corresponding":false},{"id":242235,"name":"Hongjie Li","orcid":"0000-0002-7332-7122","position":8,"is_corresponding":false},{"id":553457,"name":"Karen Menuz","orcid":"0000-0001-8163-0941","position":9,"is_corresponding":false},{"id":306025,"name":"Christopher J. Potter","orcid":"0000-0002-5223-8112","position":10,"is_corresponding":false},{"id":553453,"name":"Darya Task","orcid":"0000-0003-0166-3626","position":0,"is_corresponding":true}],"reference_count":173,"raw_metadata":null,"created_at":"2026-07-18T23:14:08.313144Z","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":[]}