{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T04:59:29Z","timestamp":1785473969569,"version":"3.56.0"},"reference-count":41,"publisher":"MDPI AG","issue":"15","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\/"}],"funder":[{"DOI":"10.13039\/501100023440","name":"Escuela Superior Polit\u00e9cnica de Chimborazo","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100023440","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/02zyw2q61","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100009092","name":"University of Alicante","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100009092","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/05t8bcz72","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100032759","name":"Universidad T\u00e9cnica Estatal de Quevedo","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100032759","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/05qrwjj27","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007064","name":"Universidad de Ja\u00e9n","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100007064","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/0122p5f64","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Ecuador ranks among the world\u2019s leading banana exporters; however, postharvest enzymatic browning, driven by polyphenol oxidases (PPOs), remains an important determinant of fruit quality loss and reduced market value. The genes encoding PPOs in Musa paradisiaca L., a triploid hybrid (AAB) widely cultivated in Ecuador, have not previously been described at the genomic or transcriptional level. The objective of this study was to generate a preliminary de novo draft assembly of Ecuadorian M. paradisiaca, identify PPO-coding loci recovered in this assembly, and compare their relative expression across three field-defined green-fruit developmental stages: early, intermediate, and physiologically mature-green. High-molecular-weight genomic DNA sequencing was performed using the Oxford Nanopore MinION Mk1B platform, and 13,239 contigs were obtained by de novo assembly with Flye v2.9.6. Two intronless PPO-coding loci, designated MpPPO1 and MpPPO2, were identified and deposited in GenBank under accessions PX565008 and PX565009. qRT-PCR showed significantly higher MpPPO1 expression at the physiologically mature-green stage, whereas MpPPO2 showed only a non-significant trend toward higher expression at the intermediate stage. These profiles indicate transcriptional divergence and identify MpPPO1 as a candidate associated with late green-fruit development or physiological maturity. However, because stage classification relied on a qualitative field harvest index and neither controlled postharvest ripening nor quantitative maturity, PPO activity, or browning measurements were performed, the results do not demonstrate ripening-induced activation, functional subfunctionalization, or causality in browning. These findings provide a preliminary molecular basis for future functional and postharvest studies in commercial banana cultivars.<\/jats:p>","DOI":"10.3390\/plants15152329","type":"journal-article","created":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T08:16:52Z","timestamp":1785313012000},"page":"2329","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Draft Genome Assembly and Differential Expression of MpPPO1 and MpPPO2 Across Green-Fruit Development in Ecuadorian Musa paradisiaca L."],"prefix":"10.3390","volume":"15","author":[{"given":"V\u00edctor","family":"Huebla-Concha","sequence":"first","affiliation":[{"name":"Biology Laboratory, Higher Polytechnic School of Chimborazo (ESPOCH), Panamericana Sur, km. 1 \u00bd, Riobamba 060155, Chimborazo, Ecuador"},{"name":"Department of Experimental Biology, University of Ja\u00e9n, Campus Las Lagunillas s\/n, 23071 Ja\u00e9n, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicol\u00e1s","family":"Cruz-Rosero","sequence":"additional","affiliation":[{"name":"Molecular Biology Laboratory, Quevedo State Technical University (UTEQ), Central Campus, Av. Quito km. 11\/2 v\u00eda Santo Domingo de los Ts\u00e1chilas, Quevedo 120550, Los R\u00edos, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7439-4784","authenticated-orcid":false,"given":"Jaime","family":"Morante-Carriel","sequence":"additional","affiliation":[{"name":"Plant Proteomics and Functional Genomics Group, Department of Biochemistry and Molecular Biology and Soil and Agricultural Chemistry, Faculty of Science, University of Alicante, Carretera San Vicente del Raspeig s\/n, 03690 San Vicente del Raspeig, Alicante, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mercedes","family":"Carranza-Pati\u00f1o","sequence":"additional","affiliation":[{"name":"Molecular Biology Laboratory, Quevedo State Technical University (UTEQ), Central Campus, Av. Quito km. 11\/2 v\u00eda Santo Domingo de los Ts\u00e1chilas, Quevedo 120550, Los R\u00edos, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3465-3766","authenticated-orcid":false,"given":"Roque","family":"Bru-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Plant Proteomics and Functional Genomics Group, Department of Biochemistry and Molecular Biology and Soil and Agricultural Chemistry, Faculty of Science, University of Alicante, Carretera San Vicente del Raspeig s\/n, 03690 San Vicente del Raspeig, Alicante, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Morante","sequence":"additional","affiliation":[{"name":"Escuela de Nutrici\u00f3n y Diet\u00e9tica, Facultad de Ciencias de la Rehabilitaci\u00f3n y Calidad de Vida, Universidad San Sebasti\u00e1n, Campus Patagonia, Lago Panguipulli, Puerto Montt 1390, Regi\u00f3n de Los Lagos, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"23","DOI":"10.18779\/cyt.v7i1.135","article-title":"Distribuci\u00f3n, localizaci\u00f3n e inhibidores de las polifenol oxidasas en frutos y vegetales usados como alimento","volume":"7","author":"Obrebska","year":"2014","journal-title":"Cienc. 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