{"doi":"10.1242/jeb.071100","title":"<b>Genetic knockdown of a single organic anion transporter alters the expression of functionally related genes in Malpighian tubules of</b><i><b>Drosophila melanogaster</b></i>","abstract":"<jats:title>SUMMARY</jats:title><jats:p>Insects excrete a wide variety of toxins via the Malpighian (renal) tubules. Previous studies have implicated three transporters in the secretion of the organic anion (OA) methotrexate (MTX) by the Drosophila Malpighian tubule: Drosophila multidrug resistance-associated protein (dMRP, CG6214), a multidrug efflux transporter (MET, CG30344), and an organic anion transporting polypeptide 58Dc (OATP58Dc, CG3380). RNA interference (RNAi) knockdown and P-element insertion mutation of single OA transporter genes were used to evaluate the importance of these three putative transporters in the secretion of MTX by the Malpighian tubules of Drosophila melanogaster. A major finding is that genetic knockdown of a single OA transporter gene leads to reductions in the expression of at least one other OA transporter gene and in secretion of MTX by Malpighian tubules isolated from flies reared on a standard diet. The pattern of changes indicates that decreases in MTX secretion do not correspond to decreases in dMRP expression in all of the RNAi lines. Genetic knockdown of a single OA transporter gene also alters the extent of upregulation of multiple OA transporter genes in the tubules in response to dietary MTX. Knockdown of dMRP is associated with a decrease in MET expression but an increase in OATP expression when flies are reared on MTX-enriched diet. Our results indicate that dMRP and MET are not the dominant MTX transporters in the tubules when flies are reared on MTX-enriched diets. At least one additional transporter, and possibly OATP, are required for MTX secretion. The implications of our results for studies using genetic knockdown techniques to identify OA transporters in whole tissues such as Malpighian tubules are discussed.</jats:p>","journal":"Journal of Experimental Biology","year":2012,"id":615800,"datarank":0.4943755299006494,"base_score":3.295836866004329,"endowment":3.295836866004329,"self_citation_contribution":0.4943755299006494,"citation_network_contribution":0.0,"self_endowment_contribution":0.4943755299006494,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":26,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1587418,"name":"Ana Campos","orcid":null,"position":1,"is_corresponding":false},{"id":213742,"name":"Michael J. O'Donnell","orcid":null,"position":2,"is_corresponding":false},{"id":1587417,"name":"Sarah Chahine","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"<b>Genetic knockdown of a single organic anion transporter alters the expression of functionally related genes in Malpighian tubules of</b><i><b>Drosophila melanogaster</b></i>","abstract":"<jats:title>SUMMARY</jats:title><jats:p>Insects excrete a wide variety of toxins via the Malpighian (renal) tubules. Previous studies have implicated three transporters in the secretion of the organic anion (OA) methotrexate (MTX) by the Drosophila Malpighian tubule: Drosophila multidrug resistance-associated protein (dMRP, CG6214), a multidrug efflux transporter (MET, CG30344), and an organic anion transporting polypeptide 58Dc (OATP58Dc, CG3380). RNA interference (RNAi) knockdown and P-element insertion mutation of single OA transporter genes were used to evaluate the importance of these three putative transporters in the secretion of MTX by the Malpighian tubules of Drosophila melanogaster. A major finding is that genetic knockdown of a single OA transporter gene leads to reductions in the expression of at least one other OA transporter gene and in secretion of MTX by Malpighian tubules isolated from flies reared on a standard diet. The pattern of changes indicates that decreases in MTX secretion do not correspond to decreases in dMRP expression in all of the RNAi lines. Genetic knockdown of a single OA transporter gene also alters the extent of upregulation of multiple OA transporter genes in the tubules in response to dietary MTX. Knockdown of dMRP is associated with a decrease in MET expression but an increase in OATP expression when flies are reared on MTX-enriched diet. Our results indicate that dMRP and MET are not the dominant MTX transporters in the tubules when flies are reared on MTX-enriched diets. At least one additional transporter, and possibly OATP, are required for MTX secretion. The implications of our results for studies using genetic knockdown techniques to identify OA transporters in whole tissues such as Malpighian tubules are discussed.</jats:p>","is_dataset_classified":null,"base_score":3.295836866004329,"endowment":3.295836866004329,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"22786636","pmcid":null,"openalex_id":"https://openalex.org/W2098738468","authors":[],"funders":[],"total_grants":0,"fwci":1.7109,"citation_percentile":0.8451101,"influential_citations":0,"citation_trend":[{"year":2012,"count":2},{"year":2013,"count":1},{"year":2014,"count":2},{"year":2016,"count":1},{"year":2017,"count":2},{"year":2018,"count":3},{"year":2019,"count":5},{"year":2020,"count":2},{"year":2021,"count":1},{"year":2022,"count":2},{"year":2023,"count":1},{"year":2024,"count":1},{"year":2025,"count":3}],"oa_status":"closed","license":null,"oa_locations":[{"url":"http://journals.biologists.com/jeb/article-pdf/215/15/2601/1280225/2601.pdf","host_type":"publisher"},{"url":"https://doi.org/10.1242/jeb.071100","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/22786636","host_type":"repository"}],"fields_of_study":["Insect-Plant Interactions and Control","Insect Resistance and Genetics","Plant and animal studies"],"mesh_terms":["Alleles","Animals","Diet","Drosophila melanogaster","Gene Expression Regulation","Malpighian Tubules","Methotrexate","RNA, Messenger","Mutagenesis, Insertional","Ion Transport","Genes, Insect","ATP-Binding Cassette Transporters","Organic Anion Transporters","Multidrug Resistance-Associated Proteins","ATP-Binding Cassette, Sub-Family C Proteins","Drosophila Proteins","RNA Interference","Gene Knockdown Techniques"],"keywords":["Gene knockdown","Malpighian tubule system","Transporter","RNA interference","Drosophila melanogaster","Biology","Secretion","Gene expression","Gene","Organic cation transport proteins","Efflux","Cell biology","Molecular biology","Genetics","Biochemistry","RNA"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-02T21:07:34.939264Z","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":[]}