{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:47:33Z","timestamp":1792792053789,"version":"4.5.0"},"reference-count":59,"publisher":"Wiley","issue":"4","license":[{"start":{"date-parts":[[2025,12,1]],"date-time":"2025-12-01T00:00:00Z","timestamp":1764547200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2025,12,1]],"date-time":"2025-12-01T00:00:00Z","timestamp":1764547200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["febs.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["FEBS Letters"],"published-print":{"date-parts":[[2026,2]]},"abstract":"<jats:p>Ribonucleotide reductases (RNRs) convert all four ribonucleotides to deoxyribonucleotides, providing essential building blocks for DNA biosynthesis and repair through radical\u2010based catalysis. These functions are key to cellular proliferation and have made RNRs well established targets for antimicrobial and antiviral drugs and combination chemotherapies. Here, we describe a novel highly sensitive one\u2010pot enzymatic assay, which amplifies RNR activity by coupling it to the synthesis of a fluorogenic RNA aptamer. We validated this approach by testing RNR activity under dNTP\u2010limiting conditions to emulate RNR's complex allosteric regulatory patterns and by detecting the dose\u2010 and time\u2010dependent inhibition of RNR by hydroxyurea. This unique assay builds on previous high\u2010throughput screening assays for investigation of RNR's catalytic mechanisms by improving sensitivity and reducing readout timeframes.<\/jats:p>\n                  <jats:p>\n                    <jats:boxed-text content-type=\"box\" position=\"anchor\">\n                      <jats:caption>\n                        <jats:title>Impact statement<\/jats:title>\n                      <\/jats:caption>\n                      <jats:p>Ribonucleotide reductases (RNRs) are essential for controlling cellular dNTP supply and are major targets in cancer, antiviral, and antimicrobial therapy. FLARE is a novel single\u2010tube, real\u2010time RNR assay, coupling dNTP synthesis to the transcription of a fluorogenic aptamer for continuous monitoring of activity, regulation, and inhibition using standard microplate readers.<\/jats:p>\n                    <\/jats:boxed-text>\n                  <\/jats:p>","DOI":"10.1002\/1873-3468.70237","type":"journal-article","created":{"date-parts":[[2025,12,1]],"date-time":"2025-12-01T14:49:36Z","timestamp":1764600576000},"page":"467-480","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Real\u2010time assay of ribonucleotide reductase activity with a fluorescent\n                    <scp>RNA<\/scp>\n                    aptamer"],"prefix":"10.1002","volume":"600","author":[{"given":"Jacopo","family":"De Capitani","sequence":"first","affiliation":[{"name":"Biomimetic Chemistry, Department of Chemistry and Chemical Biology TU Dortmund University  Dortmund 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