{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T12:03:27Z","timestamp":1789473807761,"version":"build-2803163510"},"reference-count":12,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:00:00Z","timestamp":1789430400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Genome Ed."],"abstract":"<jats:p>\n                    Phenylketonuria (PKU) remains a challenging genetic disorder due to the absence of therapeutic strategies capable of achieving sustained restoration of phenylalanine hydroxylase (PAH) function. Here, we employed an R2 retrotransposon in\n                    <jats:italic>Taeniopygia guttata<\/jats:italic>\n                    (R2Tg)-based system to enable targeted integration of exogenous PAH mRNA into the 28S ribosomal DNA (rDNA) locus of the host genome, with the goal of rescuing PAH deficiency caused by loss-of-function mutations. Experimental results demonstrated that lipid nanoparticle (LNP) delivery of R2Tg facilitated efficient site-specific integration of EGFP and PAH transgenes in mammalian cells, significantly elevating PAH mRNA and protein expression without disrupting endogenous 28S rRNA levels. These findings support the potential of this strategy as a precise genomic modification tool with promise for lifelong correction of PAH deficiency.\n                  <\/jats:p>","DOI":"10.3389\/fgeed.2026.1893815","type":"journal-article","created":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T11:07:16Z","timestamp":1789470436000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["R2Tg retrotransposon mediated targeted integration of exogenous genes into the 28S rDNA locus in mammalian cell lines for PKU gene therapy"],"prefix":"10.3389","volume":"8","author":[{"given":"Xiuyuan","family":"Wang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Bioactive Molecules and Druggability Assessment, Department of Biochemistry and Molecular Biology, Medical College of Jinan University","place":["Guangzhou, China"]},{"name":"Guangdong Engineering Technology Research Center of Drug Development for Small Nucleic Acids","place":["Guangzhou, China"]},{"name":"Antisense Biopharmaceutical Technology Co., Ltd.","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ziqi","family":"Wen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioactive Molecules and Druggability Assessment, Department of Biochemistry and Molecular Biology, Medical College of Jinan University","place":["Guangzhou, China"]},{"name":"Guangdong Engineering Technology Research Center of Drug Development for Small Nucleic Acids","place":["Guangzhou, China"]},{"name":"Antisense Biopharmaceutical Technology Co., Ltd.","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rongjun","family":"Xu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioactive Molecules and Druggability Assessment, Department of Biochemistry and Molecular Biology, Medical College of Jinan University","place":["Guangzhou, China"]},{"name":"Guangdong Engineering Technology Research Center of Drug Development for Small Nucleic Acids","place":["Guangzhou, China"]},{"name":"Antisense Biopharmaceutical Technology Co., Ltd.","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenjing","family":"Shi","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioactive Molecules and Druggability Assessment, Department of Biochemistry and Molecular Biology, Medical College of Jinan University","place":["Guangzhou, China"]},{"name":"Guangdong Engineering Technology Research Center of Drug Development for Small Nucleic Acids","place":["Guangzhou, China"]},{"name":"Antisense Biopharmaceutical Technology Co., Ltd.","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yiling","family":"Long","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioactive Molecules and Druggability Assessment, Department of Biochemistry and Molecular Biology, Medical College of Jinan University","place":["Guangzhou, China"]},{"name":"Guangdong Engineering Technology Research Center of Drug Development for Small Nucleic Acids","place":["Guangzhou, China"]},{"name":"Antisense Biopharmaceutical Technology Co., Ltd.","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xingri","family":"Zhan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioactive Molecules and Druggability Assessment, Department of Biochemistry and Molecular Biology, Medical College of Jinan University","place":["Guangzhou, China"]},{"name":"Guangdong Engineering Technology Research Center of Drug Development for Small Nucleic Acids","place":["Guangzhou, China"]},{"name":"Antisense Biopharmaceutical Technology Co., Ltd.","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rui","family":"Su","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioactive Molecules and Druggability Assessment, Department of Biochemistry and Molecular Biology, Medical College of Jinan University","place":["Guangzhou, China"]},{"name":"Guangdong Engineering Technology Research Center of Drug Development for Small Nucleic Acids","place":["Guangzhou, China"]},{"name":"Antisense Biopharmaceutical Technology Co., Ltd.","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jia","family":"Fei","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioactive Molecules and Druggability Assessment, Department of Biochemistry and Molecular Biology, Medical College of Jinan University","place":["Guangzhou, China"]},{"name":"Guangdong Engineering Technology Research Center of Drug Development for Small Nucleic Acids","place":["Guangzhou, China"]},{"name":"Antisense Biopharmaceutical Technology Co., Ltd.","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yumin","family":"Li","sequence":"additional","affiliation":[{"name":"Medical Laboratory of the Third Affiliated Hospital of Shenzhen University","place":["Shenzhen, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,15]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1417","DOI":"10.1016\/S0140-6736(10)60961-0","article-title":"Phenylketonuria","volume":"376","author":"Blau","year":"2010","journal-title":"Lancet"},{"key":"B2","doi-asserted-by":"publisher","first-page":"4674","DOI":"10.1016\/j.cell.2024.06.020","article-title":"All-RNA-mediated targeted gene integration in mammalian cells with rationally engineered R2 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Genomics"},{"key":"B4","doi-asserted-by":"publisher","first-page":"1080","DOI":"10.1038\/s41586-025-08877-4","article-title":"Reprogramming site-specific retrotransposon activity to new DNA sites","volume":"642","author":"Fell","year":"2025","journal-title":"Nature"},{"key":"B5","doi-asserted-by":"publisher","first-page":"234","DOI":"10.1016\/j.ajhg.2020.06.006","article-title":"The genetic landscape and epidemiology of phenylketonuria","volume":"107","author":"Hillert","year":"2020","journal-title":"Am. J. Hum. Genet."},{"key":"B6","doi-asserted-by":"publisher","first-page":"1078","DOI":"10.1038\/s41578-021-00358-0","article-title":"Lipid nanoparticles for mRNA delivery","volume":"6","author":"Hou","year":"2021","journal-title":"Nat. Rev. Mater"},{"key":"B7","doi-asserted-by":"publisher","first-page":"852","DOI":"10.1016\/j.tig.2017.08.008","article-title":"Gene therapy with the sleeping beauty transposon system","volume":"33","author":"Kebriaei","year":"2017","journal-title":"Trends Genet."},{"key":"B8","doi-asserted-by":"publisher","first-page":"2456","DOI":"10.3390\/ijms25052456","article-title":"Current strategies for increasing Knock-In efficiency in CRISPR\/Cas9-Based approaches","volume":"25","author":"Leal","year":"2024","journal-title":"Int. J. Mol. 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Biotechnol."},{"key":"B11","doi-asserted-by":"publisher","first-page":"801","DOI":"10.1038\/cr.2017.76","article-title":"Homology-mediated end joining-based targeted integration using CRISPR\/Cas9","volume":"27","author":"Yao","year":"2017","journal-title":"Cell Res."},{"key":"B12","doi-asserted-by":"publisher","first-page":"42","DOI":"10.1038\/s41587-024-02137-y","article-title":"Harnessing eukaryotic retroelement proteins for transgene insertion into human safe-harbor loci","volume":"43","author":"Zhang","year":"2025","journal-title":"Nat. Biotechnol."}],"container-title":["Frontiers in Genome Editing"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fgeed.2026.1893815\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T11:07:17Z","timestamp":1789470437000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fgeed.2026.1893815\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,15]]},"references-count":12,"alternative-id":["10.3389\/fgeed.2026.1893815"],"URL":"https:\/\/doi.org\/10.3389\/fgeed.2026.1893815","relation":{},"ISSN":["2673-3439"],"issn-type":[{"value":"2673-3439","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,15]]},"article-number":"1893815"}}