{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T12:12:32Z","timestamp":1785413552617,"version":"3.56.0"},"posted":{"date-parts":[[2026,1,26]]},"group-title":"Neuroscience","reference-count":61,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,1,26]],"date-time":"2026-01-26T00:00:00Z","timestamp":1769385600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"award":["R37NS069861"],"award-info":[{"award-number":["R37NS069861"]}],"id":[{"id":"https:\/\/ror.org\/01s5ya894","id-type":"ROR","asserted-by":"publisher"}]},{"award":["R01NS097750"],"award-info":[{"award-number":["R01NS097750"]}],"id":[{"id":"https:\/\/ror.org\/01s5ya894","id-type":"ROR","asserted-by":"publisher"}]},{"award":["F31NS124290"],"award-info":[{"award-number":["F31NS124290"]}],"id":[{"id":"https:\/\/ror.org\/01s5ya894","id-type":"ROR","asserted-by":"publisher"}]},{"award":["F31NS131052"],"award-info":[{"award-number":["F31NS131052"]}],"id":[{"id":"https:\/\/ror.org\/01s5ya894","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100001454","name":"American Epilepsy Society","doi-asserted-by":"crossref","award":["957615"],"award-info":[{"award-number":["957615"]}],"id":[{"id":"10.13039\/100001454","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,5,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>\n                  The dentate gyrus is a major locus for structural and synaptic reorganization in temporal lobe epilepsy. While physiological changes during epileptogensis are well characterized in the principal dentate projection neuron, granule cells (GCs), epilepsy-related changes in semilunar granule cells (SGCs), a distinct subset of dentate projection neurons, remain unknown. Using a mouse pilocarpine model of epilepsy, we show that, unlike GCs, SGCs exhibit an increase in intrinsic excitability 1 week after status epilepticus (SE). GCs, not SGCs. have a lower threshold for action potential firing in mice 1-month post-SE. Both GCs and SGCs display increased frequency of spontaneous excitatory postsynaptic currents (EPSCs) 1-week and 1-month after SE. Uniquely, SGCs received more frequent spontaneous inhibitory postsynaptic currents (sIPSCs) and exhibited smaller afferent-evoked IPSCs early after SE. Additionally, evoked EPSC amplitude in SGCs was reduced 1-month post-SE. Behaviorally, mice 1-month post-SE showed impairments in their ability to use spatial search strategies in a Barnes maze paradigm. Post-SE TRAP2::tdT mice showed reduced activity dependent neuronal ensemble labeling, with fewer tdT-labeled neurons in both task-na\u00efve and trained conditions and reduced\n                  <jats:italic>c-Fos<\/jats:italic>\n                  co-expression following task re-acquisition compared to controls. Notably, the proportion of SGCs within labeled ensembles was reduced in task-na\u00efve epileptic mice but not in trained animals. Collectively, our findings identify selective changes in SGC intrinsic excitability during epileptogenesis that could contribute to enhanced network excitability. The cell-specific alterations in SGC circuit connectivity during epileptogenesis, alongside the apparent reduction in neuronal recruitment to behavioral ensembles likely contribute to spatial navigation deficits observed in epilepsy.\n                <\/jats:p>","DOI":"10.64898\/2026.01.24.701531","type":"posted-content","created":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T06:10:17Z","timestamp":1769494217000},"source":"Crossref","is-referenced-by-count":0,"title":["Altered Physiology and Ensemble Recruitment of Dentate Gyrus Semilunar Granule Cells in a Mouse Model of Epilepsy"],"prefix":"10.64898","author":[{"given":"Laura","family":"Dovek","sequence":"first","affiliation":[{"name":"Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, California 92521"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Molecular, Cell and Systems 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