{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T20:06:44Z","timestamp":1789675604455,"version":"4.0.1"},"posted":{"date-parts":[[2026,9,17]]},"group-title":"Biochemistry","reference-count":0,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T00:00:00Z","timestamp":1789603200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"award":["GM147211"],"award-info":[{"award-number":["GM147211"]}],"id":[{"id":"https:\/\/ror.org\/04q48ey07","id-type":"ROR","asserted-by":"publisher"}]},{"award":["R35GM124838"],"award-info":[{"award-number":["R35GM124838"]}],"id":[{"id":"https:\/\/ror.org\/04q48ey07","id-type":"ROR","asserted-by":"publisher"}]},{"award":["R35GM160278"],"award-info":[{"award-number":["R35GM160278"]}],"id":[{"id":"https:\/\/ror.org\/04q48ey07","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,9,17]]},"abstract":"<jats:p>RNA cleavage and processing are highly conserved regulatory mechanisms across bacteria. We recently discovered a novel family of RNases called YicC, conserved across all bacteria but unrelated to known RNase families. The cryo-EM structure of RNA bound to Escherichia coli YicC endonuclease suggested a clamshell-like ribonuclease mechanism for cleavage, although its exact mechanism and function remain elusive. Here, we report new cryo-EM structures that provide snapshots of the closing of the complex and also capture a surprising dimeric-RNA:protein complex. We further characterize the RNA cleavage targets in solution using nuclear magnetic resonance (NMR) spectroscopy, and use all-atom molecular dynamics (MD) simulations to study Mg2+ binding. Our findings suggest that the YicC family can bind RNA hairpin structures and dimeric conformations with appropriate sequence and structural constraints, with cleavage driven strongly by Mg2+ ion localization. This study therefore provides overall insight into the novel cleavage mechanism of the highly conserved family of YicC-like endoribonucleases.<\/jats:p>","DOI":"10.64898\/2026.09.15.751841","type":"posted-content","created":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T19:20:12Z","timestamp":1789672812000},"source":"Crossref","is-referenced-by-count":0,"title":["Structural and biophysical insights into the unique RNase YicC"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3136-3280","authenticated-orcid":false,"given":"Ruoxi","family":"Wu","sequence":"first","affiliation":[{"name":"Icahn School of Medicine at Mount Sinai;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-1277-0769","authenticated-orcid":false,"given":"Harsha","family":"Venkatesh","sequence":"additional","affiliation":[{"name":"New York University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1118-7299","authenticated-orcid":false,"given":"Carisse","family":"Lansiquot","sequence":"additional","affiliation":[{"name":"Icahn School of Medicine at Mount Sinai;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah A","family":"Barnes","sequence":"additional","affiliation":[{"name":"Icahn School of Medicine at Mount Sinai;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Afrooz","family":"Golestanian","sequence":"additional","affiliation":[{"name":"Icahn School of Medicine at Mount Sinai;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4270-7242","authenticated-orcid":false,"given":"Olga","family":"Rechkoblit","sequence":"additional","affiliation":[{"name":"Icahn School of Medicine at Mount Sinai;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2084-3625","authenticated-orcid":false,"given":"Alisha N","family":"Jones","sequence":"additional","affiliation":[{"name":"New York University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David H.","family":"Bechhofer","sequence":"additional","affiliation":[{"name":"Icahn School of Medicine at Mount Sinai;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6738-2563","authenticated-orcid":false,"given":"Michael B","family":"Lazarus","sequence":"additional","affiliation":[{"name":"Icahn School of Medicine at Mount Sinai;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","container-title":[],"original-title":[],"link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.64898\/2026.09.15.751841","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T19:20:12Z","timestamp":1789672812000},"score":1,"resource":{"primary":{"URL":"http:\/\/biorxiv.org\/lookup\/doi\/10.64898\/2026.09.15.751841"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,17]]},"references-count":0,"URL":"https:\/\/doi.org\/10.64898\/2026.09.15.751841","relation":{},"subject":[],"published":{"date-parts":[[2026,9,17]]},"subtype":"preprint"}}