BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20260411T195914EDT-66945vNEnS@132.216.98.100 DTSTAMP:20260411T235914Z DESCRIPTION:Research Seminar in Chemistry with Professor Byron Purse: Fluor escent Nucleoside Analogues for Live-Cell Imaging of RNA Biology and Singl e-Molecule Studies\n\nThis Wednesday\, March 18 at 11:00am-12:00pm\, the D epartment of Chemistry is hosting a seminar on Nucleic Acids with Professo r Byron Purse.\n\nAbstract | Fluorescent nucleoside analogues have emerged as powerful molecular probes for exploring RNA biology. Nucleobase analog ue fluorophores that preserve Watson–Crick pairing offer a distinct advant age: they can be seamlessly incorporated into nucleic acids with minimal p erturbation to native structures and functions\, while enabling precise in vestigations of conformation\, dynamics\, and interactions with proteins. In this work\, we developed a suite of fluorescent nucleoside analogues wi th two main goals: (i) establishing metabolic labeling approaches for live -cell RNA imaging without cell fixation and staining\, and (ii) achieving single-molecule detection nucleic acids labeled only with fluorescent nucl eobases. For cellular imaging\, we focused on ribonucleoside analogues rec ognized by uridine-cytidine kinase 2 (UCK2) in HeLa cells. We show that tC and pyrroloC are taken up by living cells\, phosphorylated through the py rimidine salvage pathway\, and incorporated into RNA\, enabling visualizat ion of RNA synthesis\, localization\, and turnover.\n\nUsing confocal micr oscopy colocalization studies with mCherry-tagged stress granule protein G 3BP1\, P-body protein DCP1A\, and RNA helicase DDX6\, as well as selective RNA synthesis inhibitors\, we observed rRNA enrichment in previously unch aracterized cytosolic stress granules associated with DDX6—structures dist inct from canonical stress granules and P-bodies. This labeling strategy i s also compatible with nucleolar FRAP analysis\, providing quantitative in sights that support a viscoelastic model of the nucleolus\, where proteins diffuse rapidly through an RNA-dense network. In parallel\, drawing inspi ration from xanthene dyes\, we designed and synthesized ABN\, a bright tri cyclic nucleobase analogue detectable at the single-molecule level in olig onucleotides using smTIRF and fluorescence correlation spectroscopy. Colle ctively\, these developments introduce versatile new tools for probing RNA and DNA behavior from the single-molecule to the cellular scale.\n\nDetai ls\n\nDate: Wednesday\, March 18\n\nTime: 11:00AM-12:00PM\n\nLocation: Rut tan Room\, 3rd floor\, Maass Chemistry building\n\nThis is an in-person ev ent\n DTSTART:20260318T150000Z DTEND:20260318T160000Z LOCATION:Ruttan Room\, 3rd floor\, Maass Chemistry Building\, CA\, QC\, Mon treal\, H3A 0B8\, 801 rue Sherbrooke Ouest SUMMARY:Event | Nucleic Acids Seminar with Byron Purse URL:/dna-to-rna/channels/event/event-nucleic-acids-sem inar-byron-purse-371945 END:VEVENT END:VCALENDAR