{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T05:26:48Z","timestamp":1786598808267,"version":"build-2736575974"},"reference-count":38,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T00:00:00Z","timestamp":1786406400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003141","name":"Secretar\u00eda de Ciencia, Humanidades, Tecnolog\u00eda e Innovaci\u00f3n","doi-asserted-by":"crossref","award":["319996"],"award-info":[{"award-number":["319996"]}],"id":[{"id":"10.13039\/501100003141","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>Soursop (Annona muricata L.) is a climacteric tropical fruit belonging to the Annonaceae family, widely cultivated in tropical and subtropical regions due to its economic importance, nutritional value, and abundance of bioactive compounds. Its pulp is highly appreciated for fresh consumption and food processing; however, its high respiration rate and ethylene production accelerate ripening, resulting in rapid quality deterioration and a short postharvest shelf life. During ripening, soursop fruit undergoes physiological, biochemical, and molecular changes associated with organic acid metabolism, in which citrate synthase (CS) and malate dehydrogenase (MDH) play key roles within the tricarboxylic acid cycle. However, the transcriptional dynamics of genes associated with the tricarboxylic acid cycle during postharvest storage of tropical fruits remains poorly characterized. This study aimed to identify in silico genes encoding CS and MDH and to evaluate changes in physicochemical traits, enzymatic activity, and the expression of selected CS and MDH genes during postharvest storage of soursop (A. muricata) GUANAY-1 fruit. Fruits were stored at 26 \u00b1 1 \u00b0C and evaluated on days 1, 2, 3, 4, and 5. Titratable acidity, pH, total soluble solids, CS activity, MDH activity, and the expression of selected CS and MDH genes were analyzed. Physicochemical analysis showed that the major changes in acidity, TSS, and pH occurred on day 3. In silico analysis identified 16 CS genes and 47 MDH genes in soursop, whereas transcriptome analysis identified four CS genes and three MDH genes with differential expression, designated as CS1, CS2, CS3, CS4, MDH1, MDH2, and MDH3, respectively. The Neighbor-Joining analysis grouped the CS sequences into two clusters and the MDH sequences into three clusters. Differential expression analysis revealed that CS1, CS2, CS3, CS4, MDH1, MDH2, and MDH3 were upregulated on day 3 relative to day 0 of postharvest storage. Functional enrichment analysis indicated that these genes were mainly associated with cellular respiration and the tricarboxylic acid cycle. The highest CS activity was recorded on day 3, coinciding with the maximum expression of CS1, CS2, and CS4. In contrast, MDH activity peaked on day 2, whereas MDH1 and MDH2 reached their highest expression on day 3. Correlation analysis showed positive associations between CS2 and CS4 expression and both TSS and titratable acidity. Overall, these results demonstrate temporal changes in physicochemical traits, CS and MDH enzymatic activities, and the expression of selected CS and MDH genes during postharvest storage of GUANAY-1 soursop fruit.<\/jats:p>","DOI":"10.3390\/ijms27167174","type":"journal-article","created":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T10:32:16Z","timestamp":1786444336000},"page":"7174","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Dynamics of Citrate Synthase and Malate Dehydrogenase Gene Expression, Enzymatic Activity, and Physicochemical Changes During Postharvest Storage of Soursop (Annona muricata L.) GUANAY-1 Fruit"],"prefix":"10.3390","volume":"27","author":[{"given":"Vladimir","family":"Chavarin-P\u00e9rez","sequence":"first","affiliation":[{"name":"Programa de Maestr\u00eda en Ciencias en Biotecnolog\u00eda, Universidad Aut\u00f3noma de Nayarit, Carretera Tepic-Compostela, Km. 9, Xalisco 63780, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-7366-3097","authenticated-orcid":false,"given":"Lilia Aurora","family":"D\u00edaz-Rinc\u00f3n","sequence":"additional","affiliation":[{"name":"Programa de Doctorado en Ciencias Biol\u00f3gico Agropecuarias, Universidad Aut\u00f3noma de Nayarit, Carretera Tepic-Compostela, Km. 9, Xalisco 63780, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9561-0052","authenticated-orcid":false,"given":"Jos\u00e9 Orlando","family":"Jim\u00e9nez-Zurita","sequence":"additional","affiliation":[{"name":"Unidad Academica de Agricultura, Universidad Aut\u00f3noma de Nayarit, Carretera Tepic-Compostela, Km. 9, Xalisco 63780, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2594-2275","authenticated-orcid":false,"given":"Graciela Guadalupe","family":"L\u00f3pez-Guzm\u00e1n","sequence":"additional","affiliation":[{"name":"Unidad Academica de Agricultura, Universidad Aut\u00f3noma de Nayarit, Carretera Tepic-Compostela, Km. 9, Xalisco 63780, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0990-2871","authenticated-orcid":false,"given":"Gladys Alejandra","family":"Toledo-Ibarra","sequence":"additional","affiliation":[{"name":"Laboratorio Nacional de Investigaci\u00f3n para la Inocuidad Alimentaria (LANIIA)\u2014Unidad Nayarit, Universidad Aut\u00f3noma de Nayarit, Calle Tres S\/N, Colonia, Cd. Industrial, Tepic 63000, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2048-5776","authenticated-orcid":false,"given":"Cindy Sacnithe","family":"Agredano-De La Garza","sequence":"additional","affiliation":[{"name":"Estancias Posdoctorales por M\u00e9xico, Secretar\u00eda de Ciencia, Humanidades, Tecnologia e Innovacion, Coordinacion de Apoyos a Becarios e Investigadores, Direcci\u00f3n de Posgrado,\u00a0Ciudad de Mexico 03940, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2238-8475","authenticated-orcid":false,"given":"Ver\u00f3nica Alhel\u00ed","family":"Ochoa-Jim\u00e9nez","sequence":"additional","affiliation":[{"name":"Estancias Posdoctorales por M\u00e9xico, Secretar\u00eda de Ciencia, Humanidades, Tecnologia e Innovacion, Coordinacion de Apoyos a Becarios e Investigadores, Direcci\u00f3n de Posgrado,\u00a0Ciudad de Mexico 03940, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4155-0079","authenticated-orcid":false,"given":"Guillermo","family":"Berumen-Varela","sequence":"additional","affiliation":[{"name":"Programa de Maestr\u00eda en Ciencias en Biotecnolog\u00eda, Universidad Aut\u00f3noma de Nayarit, Carretera Tepic-Compostela, Km. 9, Xalisco 63780, Mexico"},{"name":"Unidad de Tecnolog\u00eda de Alimentos-Secretar\u00eda de Investigaci\u00f3n y Posgrado, Universidad Aut\u00f3noma de Nayarit, Ciudad de la Cultura SN, Tepic 63000, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,11]]},"reference":[{"key":"ref_1","first-page":"30","article-title":"Extractos de Semilla y C\u00e1scara de Guan\u00e1bana (Annona muricata L.): Evaluaci\u00f3n Fitoqu\u00edmica.","volume":"12","year":"2024","journal-title":"RIIIT Rev. Int. Investig. Innov. Tecnol\u00f3gica"},{"key":"ref_2","unstructured":"Servicio de Informaci\u00f3n Agroalimentaria y Pesquera (SIAP) (2025, December 23). Producci\u00f3n Agr\u00edcola 2025. Available online: https:\/\/nube.agricultura.gob.mx\/cierre_agricola\/."},{"key":"ref_3","first-page":"633","article-title":"Guanay-1, Guanay-2 y Guanay-3: Nuevas variedades de guan\u00e1bana para Nayarit","volume":"14","year":"2023","journal-title":"Rev. Mex. Cienc. Agric."},{"key":"ref_4","first-page":"1","article-title":"Physicochemical and physiological changes of three soursop (Annona muricata L.) varieties during postharvest storage","volume":"12","year":"2025","journal-title":"Plant Sci. Today"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1146\/annurev-genet-110410-132507","article-title":"Genetics and Control of Tomato Fruit Ripening and Quality Attributes","volume":"45","author":"Klee","year":"2011","journal-title":"Annu. Rev. Genet."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Forlani, S., Mizzotti, C., and Masiero, S. (2021). The NAC side of the fruit: Tuning of fruit development and maturation. BMC Plant Biol., 21.","DOI":"10.1186\/s12870-021-03029-y"},{"key":"ref_7","first-page":"1261","article-title":"Caracterizaci\u00f3n de frutos de guanabana (Annona muricata L.) en Tepic, Nayarit, M\u00e9xico","volume":"7","year":"2017","journal-title":"Rev. Mex. Cienc. Agric."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1016\/j.scienta.2018.10.028","article-title":"Utilization of biotechnological tools in soursop (Annona muricata L.)","volume":"245","year":"2019","journal-title":"Sci. Hortic."},{"key":"ref_9","first-page":"4089","article-title":"Poscosecha de Frutos: Maduraci\u00f3n, Ablandamiento y Control Transcripcional","volume":"8","year":"2017","journal-title":"Rev. Mex. Cienc. Agric"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"446","DOI":"10.1111\/tpj.15112","article-title":"Phytohormones in fruit development and maturation","volume":"105","author":"Fenn","year":"2021","journal-title":"Plant J."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1329","DOI":"10.1016\/j.phytochem.2009.08.006","article-title":"Regulation of malate metabolism in grape berry and other developing fruits","volume":"70","author":"Sweetman","year":"2009","journal-title":"Phytochemistry"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1451","DOI":"10.1093\/jxb\/ert035","article-title":"What controls fleshy fruit acidity? A review of malate and citrate accumulation in fruit cells","volume":"64","author":"Etienne","year":"2013","journal-title":"J. Exp. Bot."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"97","DOI":"10.5154\/r.rchsh.2015.01.004","article-title":"The organic acids that are accumulated in the flesh of fruits: Occurrence, metabolism and factors affecting their contents\u2014A review","volume":"21","author":"Famiani","year":"2015","journal-title":"Rev. Chapingo Ser. Hortic."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Batista-Silva, W., Nascimento, V.L., Medeiros, D.B., Nunes-Nesi, A., Ribeiro, D.M., Zs\u00f6g\u00f6n, A., and Ara\u00fajo, W.L. (2018). Modifications in organic acid profiles during fruit development and ripening: Correlation or causation?. Front. Plant Sci., 871.","DOI":"10.3389\/fpls.2018.01689"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Palomino-Hermosillo, Y.A., Berumen-Varela, G., Ochoa-Jim\u00e9nez, V.A., Balois-Morales, R., Jim\u00e9nez-Zurita, J.O., Bautista-Rosales, P.U., Mart\u00ednez-Gonz\u00e1lez, M.E., L\u00f3pez-Guzm\u00e1n, G.G., Cort\u00e9s-Cruz, M.A., and Guzm\u00e1n, L.F. (2022). Transcriptome Analysis of Soursop (Annona muricata L.) Fruit under Postharvest Storage Identifies Genes Families Involved in Ripening. Plants, 11.","DOI":"10.3390\/plants11141798"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1007\/s11306-024-02093-3","article-title":"Metabolomics approach for phenolic compounds profiling of soursop (Annona muricata L.) fruit during postharvest storage","volume":"20","year":"2024","journal-title":"Metabolomics"},{"key":"ref_17","first-page":"1717","article-title":"Integrative Analysis of Transcriptome and Phenolic Compounds Profile Provides Insights into the Quality of Soursop (Annona muricata L.) Fruit","volume":"93","year":"2024","journal-title":"Phyton-Int. J. Exp. Bot."},{"key":"ref_18","first-page":"e254238","article-title":"Physicochemical characterization of Annona muricata L. fruits in Jun\u00edn, Peru","volume":"42","year":"2025","journal-title":"Rev. Fac. Agron. Univ. Zulia"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"147","DOI":"10.17268\/agroind.sci.2022.02.03","article-title":"Morphological, physicochemical and health characterization of a selection of multipattern clones of soursop (Annona muricata L.)","volume":"12","year":"2022","journal-title":"Agroindustrial Sci."},{"key":"ref_20","first-page":"223","article-title":"Caracterizaci\u00f3n morfol\u00f3gica y fisicoqu\u00edmica de frutos de accesiones de guan\u00e1banas seleccionadas en Nayarit","volume":"10","year":"2019","journal-title":"Rev. Mex. Cienc. Agric."},{"key":"ref_21","first-page":"98","article-title":"Efecto de la concentraci\u00f3n de pulpa de guan\u00e1bana en las propiedades fisicoqu\u00edmicas de la bebida l\u00e1ctea refrescante a base de lactosuero dulce","volume":"14","year":"2024","journal-title":"Rev. Cienc. Tecnol. Higo"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"uhae225","DOI":"10.1093\/hr\/uhae225","article-title":"The art of tartness: The genetics of organic acid content in fresh fruits","volume":"11","author":"Miao","year":"2024","journal-title":"Hortic. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1007\/s44281-024-00044-5","article-title":"Low soil pH enhances fruit acidity by inhibiting citric acid degradation in lemon (Citrus lemon L.)","volume":"2","author":"Wu","year":"2024","journal-title":"Hortic. Adv."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"4097","DOI":"10.1093\/jxb\/eru197","article-title":"Water shortage and quality of fleshy fruits\u2014Making the most of the unavoidable","volume":"65","author":"Ripoll","year":"2014","journal-title":"J. Exp. Bot."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Li, S., Chen, K., and Grierson, D. (2021). Molecular and Hormonal Mechanisms Regulating Fleshy Fruit Ripening. Cells, 10.","DOI":"10.3390\/cells10051136"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"evab077","DOI":"10.1093\/gbe\/evab077","article-title":"Homoeolog Inference Methods Requiring Bidirectional Best Hits or Synteny Miss Many Pairs","volume":"13","author":"Glover","year":"2021","journal-title":"Genome Biol. Evol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1146\/annurev.genet.39.073003.114725","article-title":"Orthologs, Paralogs, and Evolutionary Genomics","volume":"39","author":"Koonin","year":"2005","journal-title":"Annu. Rev. Genet."},{"key":"ref_28","unstructured":"Lagreze P\u00e9rez, J.J. (2018). Dise\u00f1o Experimental para el Estudio de la Posible Funci\u00f3n de la Citrato Sintasa Mitocondrial de Annona cherimola (Ac-mCS) en la Maduraci\u00f3n de Frutos. [Bachelor\u2019s thesis, Universidad de Chile]."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Gonz\u00e1lez-Ag\u00fcero, M., Pardo, L.T., Zamudio, M.S., Contreras, C., Undurraga, P., and Defilippi, B.G. (2016). The unusual acid-accumulating behavior during ripening of cherimoya (Annona cherimola Mill.) is linked to changes in transcription and enzyme activity related to citric and malic acid metabolism. Molecules, 21.","DOI":"10.3390\/molecules21050398"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Zhai, Y., Fan, Z., Cui, Y., Gu, X., Chen, S., and Ma, H. (2022). APETALA2\/ethylene responsive factor in fruit ripening: Roles, interactions and expression regulation. Front. Plant Sci., 13.","DOI":"10.3389\/fpls.2022.979348"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"919","DOI":"10.1111\/1750-3841.16067","article-title":"Abnormal behavior of chilling injury in postharvest papaya fruit is associated with sugar metabolism","volume":"87","author":"Zhu","year":"2022","journal-title":"J. Food Sci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"108893","DOI":"10.1016\/j.scienta.2019.108893","article-title":"Identification of reference genes for quantitative real-time PCR in different developmental stages and under refrigeration conditions in soursop fruits (Annona muricata L.)","volume":"260","year":"2020","journal-title":"Sci. Hortic."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"248","DOI":"10.1016\/0003-2697(76)90527-3","article-title":"A Rapid and Sensitive Method for the Quantitation of Microgram Quantities of Protein Utilizing the Principle of Protein-Dye Binding","volume":"72","author":"Bradford","year":"1976","journal-title":"Anal. Biochem."},{"key":"ref_34","first-page":"406","article-title":"The neighbor-joining method: A new method for reconstructing phylogenetic trees","volume":"4","author":"Saitou","year":"1987","journal-title":"Mol. Biol. Evol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"550","DOI":"10.1186\/s13059-014-0550-8","article-title":"Moderated estimation of fold change and dispersion for RNA-seq data with DESeq2","volume":"15","author":"Love","year":"2014","journal-title":"Genome Biol."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"D\u00edaz-Rinc\u00f3n, L.A., Balois-Morales, R., Bautista-Rosales, P.U., Ochoa-Jim\u00e9nez, V.A., Bello-Lara, J.E., and Berumen-Varela, G. (2023). Pectin-Degrading Enzymes during Soursop (Annona muricata L.) Fruit Ripening: A Bioinformatics Approach. Horticulturae, 9.","DOI":"10.3390\/horticulturae9101150"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1016\/j.sajb.2012.08.004","article-title":"A general method for high-quality RNA isolation from metabolite-rich fruits","volume":"83","author":"Gudenschwager","year":"2012","journal-title":"S. Afr. J. Bot."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1006\/meth.2001.1262","article-title":"Analysis of Relative Gene Expression Data Using Real-Time Quantitative PCR and the 2\u2212\u0394\u0394CT Method","volume":"25","author":"Livak","year":"2001","journal-title":"Methods"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/16\/7174\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T04:27:23Z","timestamp":1786595243000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/16\/7174"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,11]]},"references-count":38,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["ijms27167174"],"URL":"https:\/\/doi.org\/10.3390\/ijms27167174","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,11]]}}}