Molecular Regulatory Mechanisms Underlying Leaf Color Transitions in Pyrus betulaefolia Bunge under High Light Intensity Stress

Molecular Regulatory Mechanisms Underlying Leaf Color Transitions in Pyrus betulaefolia Bunge under High Light Intensity Stress | 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 Research Article Molecular Regulatory Mechanisms Underlying Leaf Color Transitions in Pyrus betulaefolia Bunge under High Light Intensity Stress Changlai liu, Fanfan He, Yiqun Xu, Yingying Dai, Guohua LIU This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8489484/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Pyrus betulaefolia is a significant species within the Pyrus genus and serves as a crucial rootstock for commercial pear cultivation. While leaf coloration is a common phenomenon in nature, the specific mechanisms driving this change in P. betulaefolia remain underexplored. This study investigated leaf color dynamics in P. betulaefolia , revealing that leaves turned red following 12 days of exposure to intense white light. Subsequently, exposure to natural light for 9 days induced the red leaves to revert to green. Measurements of chlorophyll fluorescence and pigment content indicated that the reddened leaves exhibited significantly increased non-photochemical quenching (NPQ) and elevated synthesis of chlorophyll a, anthocyanins, and carotenoids, thereby enhancing their tolerance to high-intensity white light. Transcriptome analysis of the red leaves demonstrated a marked upregulation of light-harvesting complex (LHC) proteins, as well as proteins related to carotenoid and chlorophyll metabolism. Furthermore, transcription factor analysis identified 18 transcription factors potentially involved in regulating these pigment changes. Non-photochemical quenching Pyrus betulaefolia LHC proteins Transcription factors Full Text Additional Declarations No competing interests reported. Supplementary Files supplytable.xlsx figureS1.tiff figureS2.tif figureS3.png figureS4.png figureS5.png Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 06 Jan, 2026 Submission checks completed at journal 03 Jan, 2026 Editor assigned by journal 03 Jan, 2026 First submitted to journal 31 Dec, 2025 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. 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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-8489484","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":570046185,"identity":"5e336f5c-35c0-432f-b989-f7de3209f286","order_by":0,"name":"Changlai 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Stress","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"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":"bmc-plant-biology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pbio","sideBox":"Learn more about [BMC Plant Biology](http://bmcplantbiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pbio/default.aspx","title":"BMC Plant Biology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Non-photochemical quenching, Pyrus betulaefolia, LHC proteins, Transcription factors","lastPublishedDoi":"10.21203/rs.3.rs-8489484/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8489484/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e \u003cem\u003ePyrus betulaefolia\u003c/em\u003e is a significant species within the \u003cem\u003ePyrus\u003c/em\u003e genus and serves as a crucial rootstock for commercial pear cultivation. While leaf coloration is a common phenomenon in nature, the specific mechanisms driving this change in \u003cem\u003eP. betulaefolia\u003c/em\u003e remain underexplored. This study investigated leaf color dynamics in \u003cem\u003eP. betulaefolia\u003c/em\u003e, revealing that leaves turned red following 12 days of exposure to intense white light. Subsequently, exposure to natural light for 9 days induced the red leaves to revert to green. Measurements of chlorophyll fluorescence and pigment content indicated that the reddened leaves exhibited significantly increased non-photochemical quenching (NPQ) and elevated synthesis of chlorophyll a, anthocyanins, and carotenoids, thereby enhancing their tolerance to high-intensity white light. Transcriptome analysis of the red leaves demonstrated a marked upregulation of light-harvesting complex (LHC) proteins, as well as proteins related to carotenoid and chlorophyll metabolism. Furthermore, transcription factor analysis identified 18 transcription factors potentially involved in regulating these pigment changes.\u003c/p\u003e","manuscriptTitle":"Molecular Regulatory Mechanisms Underlying Leaf Color Transitions in Pyrus betulaefolia Bunge under High Light Intensity Stress","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-07 17:57:01","doi":"10.21203/rs.3.rs-8489484/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-01-06T08:10:57+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-03T05:36:47+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-03T05:36:47+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Plant Biology","date":"2025-12-31T11:43:48+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-plant-biology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pbio","sideBox":"Learn more about [BMC Plant Biology](http://bmcplantbiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pbio/default.aspx","title":"BMC Plant Biology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7bd9f3e9-72a9-49e5-b403-2cea41928898","owner":[],"postedDate":"January 7th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-01-20T15:02:55+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-07 17:57:01","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8489484","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8489484","identity":"rs-8489484","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}