{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T05:00:23Z","timestamp":1785474023125,"version":"3.56.0"},"reference-count":51,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T00:00:00Z","timestamp":1785283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Non-Coding RNA","ncRNA"],"abstract":"<jats:p>Circular RNAs (circRNAs) have recently emerged as a class of abundant and remarkably stable non-coding RNAs preferentially enriched in the nervous system. In neurons, the fine-tuned spatial regulation of gene expression is critical for proper synaptic function; accordingly, several studies have demonstrated that circRNAs exhibit highly compartmentalized localization, specifically within dendrites, axons, and synapses. These spatial localization properties imply the presence of active transport mechanisms, which control the intracellular trafficking of circRNAs. This review highlights the current understanding of circRNA transport in neurons, focusing on the molecular machinery driving synaptic enrichment. We explore the potential role of ribonucleoprotein-based transport as a primary mechanism driving circRNA localization and examine how such spatial distribution influences synaptic plasticity and post-transcriptional gene regulation. Finally, we discuss the clinical implications of these processes, exploring the link between dysregulated RNA transport and the development of neuronal abnormalities.<\/jats:p>","DOI":"10.3390\/ncrna12040027","type":"journal-article","created":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T17:01:46Z","timestamp":1785344506000},"page":"27","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Circular RNAs in Neurons: From Transport to Function"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-2737-8411","authenticated-orcid":false,"given":"Nicol\u00f2","family":"Salvi","sequence":"first","affiliation":[{"name":"Department of Biology and Biotechnologies \u201cCharles Darwin\u201d, Sapienza University of Rome, 00185 Rome, Italy"},{"name":"Center for Life Nano- and Neuro-Science, Istituto Italiano di Tecnologia, 00161 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8327-4423","authenticated-orcid":false,"given":"Mariangela","family":"Morlando","sequence":"additional","affiliation":[{"name":"Department of Biology and Biotechnologies \u201cCharles Darwin\u201d, Sapienza University of Rome, 00185 Rome, Italy"},{"name":"Center for Life Nano- and Neuro-Science, Istituto Italiano di Tecnologia, 00161 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1016\/0092-8674(91)90244-S","article-title":"Scrambled Exons","volume":"64","author":"Nigro","year":"1991","journal-title":"Cell"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5327","DOI":"10.1038\/s41467-023-40348-0","article-title":"Circular RNAs in the Human Brain Are Tailored to Neuron Identity and Neuropsychiatric Disease","volume":"14","author":"Dong","year":"2023","journal-title":"Nat. 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