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We have previously developed a syndicate of intensity-based, genetically encoded sensors based on the insertion of circularly permuted GFP into a Venus-flytrap-like analyte-binding protein. Here we use the same approach to develop an intensity-based G6P Sensing Fluorescent Reporter (iG6PSnFR). We present two variants: a G6P-activated sensor that increases fluorescence and a G6P-inactivated sensor that decreases fluorescence. We validate performance across progressively more complex preparations, including purified protein in vitro, immortalized and primary neuronal cultures, isolated pancreatic islets, in an intravital liver model, and finally in vivo in\n                  <jats:italic>C. elegans<\/jats:italic>\n                  neurons. In each context, iG6PSnFR reports G6P changes consistent with expected responses to physiological perturbations.\n                <\/jats:p>","DOI":"10.64898\/2026.07.22.740099","type":"posted-content","created":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T13:20:29Z","timestamp":1784812829000},"source":"Crossref","is-referenced-by-count":0,"title":["iG6PSnFR: A genetically encoded fluorescent sensor for observing glucose-6-phosphate dynamics in living preparations"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2294-4515","authenticated-orcid":false,"given":"Jonathan S.","family":"Marvin","sequence":"first","affiliation":[{"name":"Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anastasia","family":"Tsives","sequence":"additional","affiliation":[{"name":"Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine; New Haven, CT, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5070-1732","authenticated-orcid":false,"given":"Shih Ming","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhanat","family":"Koshenov","sequence":"additional","affiliation":[{"name":"Department of Biochemistry & Biophysics, Weill Cornell Medicine, New York, NY, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raghabendra","family":"Adhikari","sequence":"additional","affiliation":[{"name":"Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4926-5064","authenticated-orcid":false,"given":"Aaron D.","family":"Wolfe","sequence":"additional","affiliation":[{"name":"Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine; New Haven, CT, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ian J.","family":"Gonzalez","sequence":"additional","affiliation":[{"name":"Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine; New Haven, CT, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Feliciano","sequence":"additional","affiliation":[{"name":"Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2533-9548","authenticated-orcid":false,"given":"Timothy A.","family":"Ryan","sequence":"additional","affiliation":[{"name":"Department of Biochemistry & Biophysics, Weill Cornell Medicine, New York, NY, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1599-9227","authenticated-orcid":false,"given":"Matthew J.","family":"Merrins","sequence":"additional","affiliation":[{"name":"Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0223-7717","authenticated-orcid":false,"given":"Daniel A.","family":"Col\u00f3n-Ramos","sequence":"additional","affiliation":[{"name":"Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine; New Haven, CT, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Timothy A.","family":"Brown","sequence":"additional","affiliation":[{"name":"Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026072722050930000_2026.07.22.740099v1.1","doi-asserted-by":"crossref","unstructured":"F. 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