The SIRT5-SUCLG2 desuccinylation axis delays ovarian aging via a mitochondrial-epigenetic regulatory mechanism

The SIRT5-SUCLG2 desuccinylation axis delays ovarian aging via a mitochondrial-epigenetic regulatory mechanism | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article The SIRT5-SUCLG2 desuccinylation axis delays ovarian aging via a mitochondrial-epigenetic regulatory mechanism Zhongquan Zhao, Dejun Xu, Shuaifei Song, Jingmiao Shi, Zhiling Zhao, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7030863/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Mitochondrial dysfunction and epigenetic alterations play critical roles in aging-related diseases, yet the molecular mechanisms linking mito-nuclear crosstalk to ovarian aging remain poorly understood. Here, single-cell transcriptome analysis of aging ovaries revealed senescence-associated hallmark alterations, including abnormally elevated mitochondrial metabolism, disrupted histone modification patterns, and enrichment of the senescence-associated secretory phenotype (SASP). We demonstrated that impaired SIRT5-mediated desuccinylation constitutes a key driver of ovarian aging. Mechanistically, we identified succinyl-coenzyme A (CoA) synthetase GDP-forming subunit β (SUCLG2) in the tricarboxylic acid (TCA) cycle as the main target of SIRT5-mediated desuccinylation. SUCLG2 desuccinylation at lysine residues K93 and K101 enhanced its protein stability and activity, thereby improving mitochondrial function upon cellular senescence. However, SUCLG2 hypersuccinylation specifically increased H4K8ac through acetyl-CoA accumulation in nucleus, leading to the overexpression of metabolism-related genes to compensate for the energy demand deficiency caused by decreased mitochondrial function during cellular senescence. In vivo functional studies demonstrated that acetyl-CoA oversupply accelerated ovarian aging, whereas ovarian gene therapy employing a SUCLG2 desuccinylation mutant ameliorated this condition. This study illuminates the molecular mechanisms underlying ovarian aging and identifies the SIRT5-SUCLG2 axis as a promising therapeutic target for age-related ovarian dysfunction. Biological sciences/Physiology/Ageing Biological sciences/Physiology/Metabolism/Mitochondria/Energy metabolism Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryTables15.xlsx Supplementary Tables 1-5 ExtendedDateFigures.pdf Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7030863","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":496105700,"identity":"29d9f3f3-4e27-4d6d-8cbd-8c47ea68997e","order_by":0,"name":"Zhongquan Zhao","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+0lEQVRIiWNgGAWjYDACCSBmbIDxKhCCxGo5Q7IWxjYitMjPbn748OcOmzx59xzDz4Xz6hI3HGA+eJuHwS4PlxbGOceMDSTPpBUbnnljLD1z22GgFrZkax6G5GJcWpglEswkDNsOJ26ckWMgzbvtQO6GAzxm0jwMBxIbcGhhk0j/JpEI0WL8m3dOHVAL/ze8WngkcswkDgK1zAcypHkbmEG2sOHVIiGRU2zY2JaWuIHnWZk1z7HD9TMPsxlbzjFIxqlFfkb6xoc/22wS57cnb77NU1NnzHe8+eGNNxV2OLXAgcGBBFiIgLmE1IOsa0ggqGYUjIJRMApGKAAA1LBX8Rgej3oAAAAASUVORK5CYII=","orcid":"","institution":"Southwest University","correspondingAuthor":true,"prefix":"","firstName":"Zhongquan","middleName":"","lastName":"Zhao","suffix":""},{"id":496105701,"identity":"a3e5506e-55aa-4d63-beb5-83c1a3aba06d","order_by":1,"name":"Dejun Xu","email":"","orcid":"","institution":"Southwest University","correspondingAuthor":false,"prefix":"","firstName":"Dejun","middleName":"","lastName":"Xu","suffix":""},{"id":496105702,"identity":"f24d7af9-177e-41aa-98c7-6feb8d5808ae","order_by":2,"name":"Shuaifei Song","email":"","orcid":"","institution":"Southwest University","correspondingAuthor":false,"prefix":"","firstName":"Shuaifei","middleName":"","lastName":"Song","suffix":""},{"id":496105703,"identity":"12b2efcd-126d-4e8b-b5f1-dd5a1dbd0208","order_by":3,"name":"Jingmiao Shi","email":"","orcid":"","institution":"Southwest University","correspondingAuthor":false,"prefix":"","firstName":"Jingmiao","middleName":"","lastName":"Shi","suffix":""},{"id":496105704,"identity":"abb0a4fa-9c44-4394-9ccb-08a59b345409","order_by":4,"name":"Zhiling Zhao","email":"","orcid":"","institution":"Southwest University","correspondingAuthor":false,"prefix":"","firstName":"Zhiling","middleName":"","lastName":"Zhao","suffix":""},{"id":496105705,"identity":"26b6a222-8afc-4844-b498-342e4d8d1736","order_by":5,"name":"Lei Wang","email":"","orcid":"","institution":"Southwest University","correspondingAuthor":false,"prefix":"","firstName":"Lei","middleName":"","lastName":"Wang","suffix":""},{"id":496105706,"identity":"478cc2ce-8832-4f68-8fc9-e17301bd5870","order_by":6,"name":"Yanguo Han","email":"","orcid":"","institution":"Southwest University","correspondingAuthor":false,"prefix":"","firstName":"Yanguo","middleName":"","lastName":"Han","suffix":""},{"id":496105707,"identity":"8c5f0967-2452-4520-8abb-fcc5cde19e26","order_by":7,"name":"Guangxin E","email":"","orcid":"","institution":"Southwest University","correspondingAuthor":false,"prefix":"","firstName":"Guangxin","middleName":"","lastName":"E","suffix":""},{"id":496105708,"identity":"158629b0-aa80-4dfd-a2f6-47af72b983ae","order_by":8,"name":"Yongju Zhao","email":"","orcid":"","institution":"Southwest University","correspondingAuthor":false,"prefix":"","firstName":"Yongju","middleName":"","lastName":"Zhao","suffix":""}],"badges":[],"createdAt":"2025-07-02 15:30:38","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7030863/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7030863/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":90666085,"identity":"0d3e761f-743c-4a4f-92eb-1f569345ca71","added_by":"auto","created_at":"2025-09-05 12:39:42","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3375306,"visible":true,"origin":"","legend":"Article File","description":"","filename":"Manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7030863/v1_covered_3685979c-b2d2-44d2-8978-db5d5a98a651.pdf"},{"id":88417018,"identity":"f8fc59fe-7a49-4fe4-8236-08a4b94455c7","added_by":"auto","created_at":"2025-08-06 09:06:26","extension":"xlsx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":925003,"visible":true,"origin":"","legend":"Supplementary Tables 1-5","description":"","filename":"SupplementaryTables15.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-7030863/v1/fe1e7a893bca181299958ffc.xlsx"},{"id":88418532,"identity":"4875b936-739e-4c58-8150-29874f6b2f94","added_by":"auto","created_at":"2025-08-06 09:14:26","extension":"pdf","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":2502955,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"ExtendedDateFigures.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7030863/v1/983936e219c1b410a599aefa.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"The SIRT5-SUCLG2 desuccinylation axis delays ovarian aging via a mitochondrial-epigenetic regulatory mechanism","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7030863/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7030863/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Mitochondrial dysfunction and epigenetic alterations play critical roles in aging-related diseases, yet the molecular mechanisms linking mito-nuclear crosstalk to ovarian aging remain poorly understood. Here, single-cell transcriptome analysis of aging ovaries revealed senescence-associated hallmark alterations, including abnormally elevated mitochondrial metabolism, disrupted histone modification patterns, and enrichment of the senescence-associated secretory phenotype (SASP). We demonstrated that impaired SIRT5-mediated desuccinylation constitutes a key driver of ovarian aging. Mechanistically, we identified succinyl-coenzyme A (CoA) synthetase GDP-forming subunit β (SUCLG2) in the tricarboxylic acid (TCA) cycle as the main target of SIRT5-mediated desuccinylation. SUCLG2 desuccinylation at lysine residues K93 and K101 enhanced its protein stability and activity, thereby improving mitochondrial function upon cellular senescence. However, SUCLG2 hypersuccinylation specifically increased H4K8ac through acetyl-CoA accumulation in nucleus, leading to the overexpression of metabolism-related genes to compensate for the energy demand deficiency caused by decreased mitochondrial function during cellular senescence. In vivo functional studies demonstrated that acetyl-CoA oversupply accelerated ovarian aging, whereas ovarian gene therapy employing a SUCLG2 desuccinylation mutant ameliorated this condition. This study illuminates the molecular mechanisms underlying ovarian aging and identifies the SIRT5-SUCLG2 axis as a promising therapeutic target for age-related ovarian dysfunction.","manuscriptTitle":"The SIRT5-SUCLG2 desuccinylation axis delays ovarian aging via a mitochondrial-epigenetic regulatory mechanism","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-06 09:06:21","doi":"10.21203/rs.3.rs-7030863/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"531f8fbb-00d7-4914-87c1-240a2c9a2e68","owner":[],"postedDate":"August 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":52691516,"name":"Biological sciences/Physiology/Ageing"},{"id":52691517,"name":"Biological sciences/Physiology/Metabolism/Mitochondria/Energy metabolism"}],"tags":[],"updatedAt":"2025-09-05T12:31:29+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-06 09:06:21","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7030863","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7030863","identity":"rs-7030863","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}