{"title":"柑橘多胚基因CitRWP激活替代性NAD(P)H脱氢酶,触发H2O2积累","authors":"Chunming Tan, Wanqi Ai, Meizhen Song, Gang Hu, Xiang Zhang, Huilan Liu, Huihui Jia, Zhixiong Rao, Xia Wang, Zongcheng Lin, Yuantao Xu, Qiang Xu","doi":"10.1016/j.hpj.2025.07.008","DOIUrl":null,"url":null,"abstract":"Citrus exhibits polyembryony, a form of sporophytic apomixis, which involves development of nucellar cells into embryos. Recent genetic mapping identified CitRWP, an RWP-RK transcription factor as a key regulator of polyembryony, however, there is lack of homozygous genotype of <ce:italic>CitRWP</ce:italic> and its promoter in nature. The mechanism of this phenomenon remains unclear. Here, we demonstrate that overexpression of <ce:italic>CitRWP</ce:italic> induces somatic embryogenesis in <ce:italic>Arabidopsis</ce:italic> roots and leads to the accumulation of reactive oxygen species (ROS) and cell death in vegetative tissues of <ce:italic>Fortunella hindsii</ce:italic>. Transcriptomic analysis of <ce:italic>CitRWP</ce:italic>-overexpressing leaves revealed enrichment of differentially expressed genes involved in ROS metabolism, redox regulation, and antioxidant defense pathways. Analysis of the <ce:italic>CitRWP</ce:italic> promoter with miniature inverted-repeat transposable element (MITE) insertion revealed that no homozygous genotypes were detected among the artificially generated hybrid progeny, which is indicative of lethality of the <ce:italic>CitRWP</ce:italic>-overexpressing genotype. Luciferase assay, Electrophoretic Mobility Shift Assay, and CUT&Tag-qPCR confirmed that CitRWP directly binds to and activates the alternative NAD(P)H dehydrogenase (<ce:italic>NDA</ce:italic>) promoter. Overexpression of <ce:italic>NDA</ce:italic> in <ce:italic>F. hindsii</ce:italic> resulted in H<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">2</ce:inf> accumulation, leaf chlorosis, and growth inhibition. Our results indicate that CitRWP promotes H<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">2</ce:inf> production via <ce:italic>NDA</ce:italic> activation, providing new insights into its regulatory role in citrus polyembryony.","PeriodicalId":13178,"journal":{"name":"Horticultural Plant Journal","volume":"39 1","pages":""},"PeriodicalIF":6.2000,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Citrus polyembryony gene CitRWP activates alternative NAD(P)H dehydrogenase and triggers H2O2 accumulation\",\"authors\":\"Chunming Tan, Wanqi Ai, Meizhen Song, Gang Hu, Xiang Zhang, Huilan Liu, Huihui Jia, Zhixiong Rao, Xia Wang, Zongcheng Lin, Yuantao Xu, Qiang Xu\",\"doi\":\"10.1016/j.hpj.2025.07.008\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Citrus exhibits polyembryony, a form of sporophytic apomixis, which involves development of nucellar cells into embryos. Recent genetic mapping identified CitRWP, an RWP-RK transcription factor as a key regulator of polyembryony, however, there is lack of homozygous genotype of <ce:italic>CitRWP</ce:italic> and its promoter in nature. The mechanism of this phenomenon remains unclear. Here, we demonstrate that overexpression of <ce:italic>CitRWP</ce:italic> induces somatic embryogenesis in <ce:italic>Arabidopsis</ce:italic> roots and leads to the accumulation of reactive oxygen species (ROS) and cell death in vegetative tissues of <ce:italic>Fortunella hindsii</ce:italic>. Transcriptomic analysis of <ce:italic>CitRWP</ce:italic>-overexpressing leaves revealed enrichment of differentially expressed genes involved in ROS metabolism, redox regulation, and antioxidant defense pathways. Analysis of the <ce:italic>CitRWP</ce:italic> promoter with miniature inverted-repeat transposable element (MITE) insertion revealed that no homozygous genotypes were detected among the artificially generated hybrid progeny, which is indicative of lethality of the <ce:italic>CitRWP</ce:italic>-overexpressing genotype. Luciferase assay, Electrophoretic Mobility Shift Assay, and CUT&Tag-qPCR confirmed that CitRWP directly binds to and activates the alternative NAD(P)H dehydrogenase (<ce:italic>NDA</ce:italic>) promoter. Overexpression of <ce:italic>NDA</ce:italic> in <ce:italic>F. hindsii</ce:italic> resulted in H<ce:inf loc=\\\"post\\\">2</ce:inf>O<ce:inf loc=\\\"post\\\">2</ce:inf> accumulation, leaf chlorosis, and growth inhibition. Our results indicate that CitRWP promotes H<ce:inf loc=\\\"post\\\">2</ce:inf>O<ce:inf loc=\\\"post\\\">2</ce:inf> production via <ce:italic>NDA</ce:italic> activation, providing new insights into its regulatory role in citrus polyembryony.\",\"PeriodicalId\":13178,\"journal\":{\"name\":\"Horticultural Plant Journal\",\"volume\":\"39 1\",\"pages\":\"\"},\"PeriodicalIF\":6.2000,\"publicationDate\":\"2025-09-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Horticultural Plant Journal\",\"FirstCategoryId\":\"97\",\"ListUrlMain\":\"https://doi.org/10.1016/j.hpj.2025.07.008\",\"RegionNum\":1,\"RegionCategory\":\"农林科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"HORTICULTURE\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Horticultural Plant Journal","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1016/j.hpj.2025.07.008","RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"HORTICULTURE","Score":null,"Total":0}
Citrus polyembryony gene CitRWP activates alternative NAD(P)H dehydrogenase and triggers H2O2 accumulation
Citrus exhibits polyembryony, a form of sporophytic apomixis, which involves development of nucellar cells into embryos. Recent genetic mapping identified CitRWP, an RWP-RK transcription factor as a key regulator of polyembryony, however, there is lack of homozygous genotype of CitRWP and its promoter in nature. The mechanism of this phenomenon remains unclear. Here, we demonstrate that overexpression of CitRWP induces somatic embryogenesis in Arabidopsis roots and leads to the accumulation of reactive oxygen species (ROS) and cell death in vegetative tissues of Fortunella hindsii. Transcriptomic analysis of CitRWP-overexpressing leaves revealed enrichment of differentially expressed genes involved in ROS metabolism, redox regulation, and antioxidant defense pathways. Analysis of the CitRWP promoter with miniature inverted-repeat transposable element (MITE) insertion revealed that no homozygous genotypes were detected among the artificially generated hybrid progeny, which is indicative of lethality of the CitRWP-overexpressing genotype. Luciferase assay, Electrophoretic Mobility Shift Assay, and CUT&Tag-qPCR confirmed that CitRWP directly binds to and activates the alternative NAD(P)H dehydrogenase (NDA) promoter. Overexpression of NDA in F. hindsii resulted in H2O2 accumulation, leaf chlorosis, and growth inhibition. Our results indicate that CitRWP promotes H2O2 production via NDA activation, providing new insights into its regulatory role in citrus polyembryony.
期刊介绍:
Horticultural Plant Journal (HPJ) is an OPEN ACCESS international journal. HPJ publishes research related to all horticultural plants, including fruits, vegetables, ornamental plants, tea plants, and medicinal plants, etc. The journal covers all aspects of horticultural crop sciences, including germplasm resources, genetics and breeding, tillage and cultivation, physiology and biochemistry, ecology, genomics, biotechnology, plant protection, postharvest processing, etc. Article types include Original research papers, Reviews, and Short communications.