{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T00:42:00Z","timestamp":1770424920259,"version":"3.49.0"},"posted":{"date-parts":[[2025,10,6]]},"group-title":"Cell Biology","reference-count":54,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2025,10,6]],"date-time":"2025-10-06T00:00:00Z","timestamp":1759708800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2025,10,6]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                <jats:p>\n                  Treatment of schistosomiasis, a prevalent neglected tropical disease, relies precariously on a single drug. The discovery and development of alternative anti-schistosomal small molecules most often relies on phenotypic (whole-organism) screening, whereas target- or \u201cprotein-first\u201d-based discovery options are hampered by a paucity of genetic interrogation strategies and a complex biology. Here, we demonstrate the application of photoaffinity labeling (PAL) as a chemical biology strategy to probe protein target-ligand interactions in the schistosome. Using a triazolopyrimidine (TPD) probe that binds tubulin, we established a PAL workflow with living\n                  <jats:italic>Schistosoma mansoni<\/jats:italic>\n                  worms. The probe elicited deleterious phenotypic responses consistent with the TPD series and, upon UV light activation, covalently labeled tubulin as identified by proteomics. Specific concentration-dependent engagement of tubulin was confirmed using a photostable competitor TPD. When applied directly to worm lysates, the PAL workflow produced non-specific labeling, suggesting that the conformation of the protein target is important for ligand binding. The successful application of PAL for a metazoan is, to our knowledge, novel, and the platform should prove generally applicable to identifying potential drug targets, and exploring protein-ligand interactions, in schistosomes and other organisms.\n                <\/jats:p>","DOI":"10.1101\/2025.10.04.680471","type":"posted-content","created":{"date-parts":[[2025,10,6]],"date-time":"2025-10-06T15:35:12Z","timestamp":1759764912000},"source":"Crossref","is-referenced-by-count":1,"title":["Photoaffinity labeling of protein targets in a complex metazoan: proof-of-concept using a probe for\n                  <i>Schistosoma mansoni<\/i>\n                  tubulin"],"prefix":"10.64898","author":[{"given":"Bobby","family":"Lucero","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thibault","family":"Alle","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marianna","family":"Bufano","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuemang","family":"Yao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kurt R.","family":"Brunden","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrea","family":"Brancale","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carlo","family":"Ballatore","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karol R.","family":"Francisco","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Conor R.","family":"Caffrey","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"54368","reference":[{"issue":"1","key":"2025100900251338000_2025.10.04.680471v1.1","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1038\/s41572-018-0013-8","article-title":"Schistosomiasis","volume":"4","year":"2018","journal-title":"Nat Rev Dis Primers"},{"key":"2025100900251338000_2025.10.04.680471v1.2","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(24)02814-9"},{"key":"2025100900251338000_2025.10.04.680471v1.3","unstructured":"Schistosomiasis; 2023. https:\/\/www.who.int\/news-room\/fact-sheets\/detail\/schistosomiasis."},{"issue":"1","key":"2025100900251338000_2025.10.04.680471v1.4","doi-asserted-by":"crossref","first-page":"134","DOI":"10.1186\/s40249-021-00919-z","article-title":"The economic impact of schistosomiasis","volume":"10","year":"2021","journal-title":"Infect Dis Poverty"},{"key":"2025100900251338000_2025.10.04.680471v1.5","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2411838121"},{"key":"2025100900251338000_2025.10.04.680471v1.6","doi-asserted-by":"publisher","DOI":"10.1002\/med.2610030204"},{"issue":"12","key":"2025100900251338000_2025.10.04.680471v1.7","doi-asserted-by":"crossref","first-page":"e202300154","DOI":"10.1002\/cmdc.202300154","article-title":"Praziquantel - 50 Years of Research","volume":"18","year":"2023","journal-title":"ChemMedChem"},{"issue":"1","key":"2025100900251338000_2025.10.04.680471v1.8","doi-asserted-by":"crossref","first-page":"4642","DOI":"10.1038\/s41598-024-84621-8","article-title":"Efficacy of single dose praziquantel against Schistosoma mansoni in East Africa: a systematic review and meta-analysis","volume":"15","year":"2025","journal-title":"Sci Rep"},{"key":"2025100900251338000_2025.10.04.680471v1.9","first-page":"2625255","article-title":"Efficacy of Praziquantel for the Treatment of Human Schistosomiasis in Ethiopia: A Systematic Review and Meta-Analysis","volume":"2021","year":"2021","journal-title":"J Trop Med"},{"key":"2025100900251338000_2025.10.04.680471v1.10","doi-asserted-by":"publisher","DOI":"10.1016\/0014-4894(86)90184-0"},{"key":"2025100900251338000_2025.10.04.680471v1.11","doi-asserted-by":"publisher","DOI":"10.1007\/BF00389899"},{"key":"2025100900251338000_2025.10.04.680471v1.12","doi-asserted-by":"crossref","unstructured":"Bustinduy AL , Waterhouse D , de Sousa-Figueiredo JC , et al. Population Pharmacokinetics and Pharmacodynamics of Praziquantel in Ugandan Children with Intestinal Schistosomiasis: Higher Dosages Are Required for Maximal Efficacy. mBio. 2016;7(4).","DOI":"10.1128\/mBio.00227-16"},{"key":"2025100900251338000_2025.10.04.680471v1.13","doi-asserted-by":"publisher","DOI":"10.1016\/0163-7258(85)90020-8"},{"key":"2025100900251338000_2025.10.04.680471v1.14","doi-asserted-by":"crossref","first-page":"1471451","DOI":"10.3389\/fpara.2024.1471451","article-title":"Praziquantel resistance in schistosomes: a brief report","volume":"3","year":"2024","journal-title":"Front Parasitol"},{"key":"2025100900251338000_2025.10.04.680471v1.15","doi-asserted-by":"publisher","DOI":"10.1645\/14-703.1"},{"key":"2025100900251338000_2025.10.04.680471v1.16","doi-asserted-by":"publisher","DOI":"10.1016\/j.cbpa.2007.05.031"},{"key":"2025100900251338000_2025.10.04.680471v1.17","first-page":"187","article-title":"Drug Discovery and Development for Schistosomiasis","volume":"77","year":"2019","journal-title":"Neglected Tropical Diseases: Drug Discovery and Development"},{"key":"2025100900251338000_2025.10.04.680471v1.18","doi-asserted-by":"crossref","unstructured":"Kalinna BH , Ross AG , Walduck AK . Schistosome Transgenesis: The Long Road to Success. Biology (Basel). 2024;13(1).","DOI":"10.3390\/biology13010048"},{"issue":"1","key":"2025100900251338000_2025.10.04.680471v1.19","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1038\/s41392-023-01309-7","article-title":"CRISPR\/Cas9 therapeutics: progress and prospects","volume":"8","year":"2023","journal-title":"Signal Transduct Target Ther"},{"key":"2025100900251338000_2025.10.04.680471v1.20","doi-asserted-by":"publisher","DOI":"10.1038\/s41573-019-0017-4"},{"issue":"3","key":"2025100900251338000_2025.10.04.680471v1.21","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1016\/j.jmii.2025.01.005","article-title":"RNA interference in protozoan parasites and its application","volume":"58","year":"2025","journal-title":"J Microbiol Immunol Infect"},{"issue":"4","key":"2025100900251338000_2025.10.04.680471v1.22","doi-asserted-by":"crossref","first-page":"1204","DOI":"10.1007\/s12639-022-01534-x","article-title":"CRISPR-Cas9: Taming protozoan parasites with bacterial scissor","volume":"46","year":"2022","journal-title":"J Parasit Dis"},{"key":"2025100900251338000_2025.10.04.680471v1.23","doi-asserted-by":"publisher","DOI":"10.1534\/genetics.119.301506"},{"key":"2025100900251338000_2025.10.04.680471v1.24","doi-asserted-by":"publisher","DOI":"10.3389\/fgene.2015.00144"},{"issue":"11","key":"2025100900251338000_2025.10.04.680471v1.25","doi-asserted-by":"crossref","first-page":"1016","DOI":"10.1016\/j.pt.2024.09.010","article-title":"CRISPR-based functional genomics for schistosomes and related flatworms","volume":"40","year":"2024","journal-title":"Trends Parasitol"},{"issue":"1","key":"2025100900251338000_2025.10.04.680471v1.26","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1186\/s13071-022-05211-z","article-title":"Transgenesis in parasitic helminths: a brief history and prospects for the future","volume":"15","year":"2022","journal-title":"Parasit Vectors"},{"key":"2025100900251338000_2025.10.04.680471v1.27","doi-asserted-by":"publisher","DOI":"10.1016\/S0020-7519(03)00030-4"},{"key":"2025100900251338000_2025.10.04.680471v1.28","doi-asserted-by":"publisher","DOI":"10.1016\/S0166-6851(03)00078-1"},{"issue":"2","key":"2025100900251338000_2025.10.04.680471v1.29","doi-asserted-by":"crossref","first-page":"1004","DOI":"10.1016\/j.bbrc.2018.06.109","article-title":"RNA interference in vivo in Schistosoma japonicum: Establishing and optimization of RNAi mediated suppression of gene expression by long dsRNA in the intra-mammalian life stages of worms","volume":"503","year":"2018","journal-title":"Biochem Biophys Res Commun"},{"key":"2025100900251338000_2025.10.04.680471v1.30","doi-asserted-by":"publisher","DOI":"10.1126\/science.abb7699"},{"issue":"35","key":"2025100900251338000_2025.10.04.680471v1.31","doi-asserted-by":"crossref","first-page":"e2505710122","DOI":"10.1073\/pnas.2505710122","article-title":"A genome-scale drug discovery pipeline uncovers therapeutic targets and a unique p97 allosteric binding site","volume":"122","year":"2025","journal-title":"Proc Natl Acad Sci U S A"},{"issue":"3","key":"2025100900251338000_2025.10.04.680471v1.32","doi-asserted-by":"crossref","first-page":"e1013014","DOI":"10.1371\/journal.ppat.1013014","article-title":"RNAi screening of uncharacterized genes identifies promising druggable targets in Schistosoma japonicum","volume":"21","year":"2025","journal-title":"PLoS Pathog"},{"issue":"5","key":"2025100900251338000_2025.10.04.680471v1.33","doi-asserted-by":"crossref","first-page":"1089","DOI":"10.1021\/acsinfecdis.0c00508","article-title":"Congeners Derived from Microtubule-Active Phenylpyrimidines Produce a Potent and Long-Lasting Paralysis of Schistosoma mansoni In Vitro","volume":"7","year":"2021","journal-title":"ACS Infect Dis"},{"issue":"20","key":"2025100900251338000_2025.10.04.680471v1.34","doi-asserted-by":"crossref","first-page":"e202300193","DOI":"10.1002\/cmdc.202300193","article-title":"Structure-Activity Relationships, Tolerability and Efficacy of Microtubule-Active 1,2,4-Triazolo[1,5-a]pyrimidines as Potential Candidates to Treat Human African Trypanosomiasis","volume":"18","year":"2023","journal-title":"ChemMedChem"},{"issue":"8","key":"2025100900251338000_2025.10.04.680471v1.35","doi-asserted-by":"crossref","first-page":"e202300656","DOI":"10.1002\/cmdc.202300656","article-title":"Design, Synthesis, and Evaluation of An Anti-trypanosomal [1,2,4]Triazolo[1,5-a]pyrimidine Probe for Photoaffinity Labeling Studies","volume":"19","year":"2024","journal-title":"ChemMedChem"},{"key":"2025100900251338000_2025.10.04.680471v1.36","doi-asserted-by":"publisher","DOI":"10.1016\/j.bmcl.2018.05.010"},{"issue":"1","key":"2025100900251338000_2025.10.04.680471v1.37","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1021\/acs.jmedchem.2c01411","article-title":"Microtubule-Stabilizing 1,2,4-Triazolo[1,5-a]pyrimidines as Candidate Therapeutics for Neurodegenerative Disease: Matched Molecular Pair Analyses and Computational Studies Reveal New Structure\u2013Activity Insights","volume":"66","year":"2023","journal-title":"J Med Chem"},{"issue":"6","key":"2025100900251338000_2025.10.04.680471v1.38","doi-asserted-by":"crossref","first-page":"737","DOI":"10.1016\/j.chembiol.2017.05.016","article-title":"Triazolopyrimidines Are Microtubule-Stabilizing Agents that Bind the Vinca Inhibitor Site of Tubulin","volume":"24","year":"2017","journal-title":"Cell Chem Biol"},{"key":"2025100900251338000_2025.10.04.680471v1.39","doi-asserted-by":"crossref","unstructured":"Yang J , Yu Y , Li Y , et al. Cevipabulin-tubulin complex reveals a novel agent binding site on \u03b1-tubulin with tubulin degradation effect. Sci Adv. 2021;7(21).","DOI":"10.1126\/sciadv.abg4168"},{"key":"2025100900251338000_2025.10.04.680471v1.40","doi-asserted-by":"publisher","DOI":"10.1124\/jpet.115.231175"},{"key":"2025100900251338000_2025.10.04.680471v1.41","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pntd.0000478"},{"key":"2025100900251338000_2025.10.04.680471v1.42","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pntd.0005680"},{"key":"2025100900251338000_2025.10.04.680471v1.43","doi-asserted-by":"publisher","DOI":"10.1016\/j.bmcl.2023.129123"},{"key":"2025100900251338000_2025.10.04.680471v1.44","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1002\/9780470559277.ch090167","article-title":"Target Identification by Diazirine Photo-Cross-linking and Click Chemistry","volume":"1","year":"2009","journal-title":"Curr Protoc Chem Biol"},{"key":"2025100900251338000_2025.10.04.680471v1.45","doi-asserted-by":"publisher","DOI":"10.1002\/1521-3773(20010601)40:11&lt;2004::Aid-Anie2004&gt;3.0.Co;2-5"},{"key":"2025100900251338000_2025.10.04.680471v1.46","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pmed.0040014"},{"key":"2025100900251338000_2025.10.04.680471v1.47","unstructured":"Schr\u00f6dinger Release 2024-3: MacroModel. New York, NY: Maestro, Schr\u00f6dinger, LLC; 2024."},{"key":"2025100900251338000_2025.10.04.680471v1.48","unstructured":"Schr\u00f6dinger Release 2024-3: Protein Preparation Workflow; Epik. New York, NY: Maestro, Schr\u00f6dinger, LLC; 2024."},{"key":"2025100900251338000_2025.10.04.680471v1.49","unstructured":"Schr\u00f6dinger Release 2024-3: Glide. New York, NY: Maestro, Schr\u00f6dinger, LLC; 2024."},{"key":"2025100900251338000_2025.10.04.680471v1.50","unstructured":"Schr\u00f6dinger Release 2024-3: Prime. New York, NY: Maestro, Schr\u00f6dinger, LLC; 2024."},{"key":"2025100900251338000_2025.10.04.680471v1.51","unstructured":"The PyMOL Molecular Graphics System, Version 2.0 Schr\u00f6dinger, LLC."},{"key":"2025100900251338000_2025.10.04.680471v1.52","doi-asserted-by":"publisher","DOI":"10.2307\/3280632"},{"key":"2025100900251338000_2025.10.04.680471v1.53","doi-asserted-by":"publisher","DOI":"10.1021\/ol0493094"},{"key":"2025100900251338000_2025.10.04.680471v1.54","doi-asserted-by":"crossref","unstructured":"Zhang J , Xin L , Shan B , et al. PEAKS DB: de novo sequencing assisted database search for sensitive and accurate peptide identification. Mol Cell Proteomics. 2012;11(4): M111.010587.","DOI":"10.1074\/mcp.M111.010587"}],"container-title":[],"original-title":[],"link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1101\/2025.10.04.680471","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T09:44:40Z","timestamp":1768470280000},"score":1,"resource":{"primary":{"URL":"http:\/\/biorxiv.org\/lookup\/doi\/10.1101\/2025.10.04.680471"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,10,6]]},"references-count":54,"URL":"https:\/\/doi.org\/10.1101\/2025.10.04.680471","relation":{},"subject":[],"published":{"date-parts":[[2025,10,6]]},"subtype":"preprint"}}