{"title":"Genome-wide identification of carotenoid cleavage oxygenase genes in Orah mandarin and the mechanism by which CrCCD4b1 affects peel color","authors":"","doi":"10.1016/j.scienta.2024.113652","DOIUrl":null,"url":null,"abstract":"<div><p>Color is a crucial component of the commercial value of citrus fruits. Carotenoid cleavage oxygenases (<em>CCOs</em>) can affect fruit color by oxidative cleavage of different carotenoid sites, resulting in various colors. This study proposed a genome-wide analysis of the Orah mandarin CCO gene family using bioinformatics methods and combined physiological, transcriptomic, and metabolomic data to analyze the gene expression levels and carotenoid accumulation mechanisms of different colored peel. A total of 14 <em>CCOs</em> were identified in the Orah mandarin genome. Phylogenetic analysis revealed that <em>CrCCOs</em> can be classified into six subfamilies, and the gene structure and conserved motifs support the above classification. GO and KEGG functional annotation revealed that Orah mandarin <em>CCO</em> genes play crucial roles in carotenoid synthesis and catabolism. Transcriptomic data showed that the expression level of <em>CrCCD4b1</em> was positively correlated with the current status of Orah mandarin red flavedo. Physiological and metabolomic studies further revealed that apocarotenal and β-citraurin were identified as the key metabolites controlling the change in flavedo color from yellow to red. Correlation analysis revealed <em>CrCCD4b1</em> as a crucial gene in the apocarotenal and β-citraurin expression network. For the first time, we proposed <em>CrCCD4b1</em> as a potential model for increasing red carotenoid accumulation in the flavedo by promoting the biosynthesis of C30 carotenoids (apocarotenal, β-citraurin) in Orah mandarin. This study will lay the foundation for further research on the causes of differences in peel color and the mining of crucial genes regulating the red trait.</p></div>","PeriodicalId":21679,"journal":{"name":"Scientia Horticulturae","volume":null,"pages":null},"PeriodicalIF":3.9000,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Scientia Horticulturae","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0304423824008057","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"HORTICULTURE","Score":null,"Total":0}
引用次数: 0
Abstract
Color is a crucial component of the commercial value of citrus fruits. Carotenoid cleavage oxygenases (CCOs) can affect fruit color by oxidative cleavage of different carotenoid sites, resulting in various colors. This study proposed a genome-wide analysis of the Orah mandarin CCO gene family using bioinformatics methods and combined physiological, transcriptomic, and metabolomic data to analyze the gene expression levels and carotenoid accumulation mechanisms of different colored peel. A total of 14 CCOs were identified in the Orah mandarin genome. Phylogenetic analysis revealed that CrCCOs can be classified into six subfamilies, and the gene structure and conserved motifs support the above classification. GO and KEGG functional annotation revealed that Orah mandarin CCO genes play crucial roles in carotenoid synthesis and catabolism. Transcriptomic data showed that the expression level of CrCCD4b1 was positively correlated with the current status of Orah mandarin red flavedo. Physiological and metabolomic studies further revealed that apocarotenal and β-citraurin were identified as the key metabolites controlling the change in flavedo color from yellow to red. Correlation analysis revealed CrCCD4b1 as a crucial gene in the apocarotenal and β-citraurin expression network. For the first time, we proposed CrCCD4b1 as a potential model for increasing red carotenoid accumulation in the flavedo by promoting the biosynthesis of C30 carotenoids (apocarotenal, β-citraurin) in Orah mandarin. This study will lay the foundation for further research on the causes of differences in peel color and the mining of crucial genes regulating the red trait.
期刊介绍:
Scientia Horticulturae is an international journal publishing research related to horticultural crops. Articles in the journal deal with open or protected production of vegetables, fruits, edible fungi and ornamentals under temperate, subtropical and tropical conditions. Papers in related areas (biochemistry, micropropagation, soil science, plant breeding, plant physiology, phytopathology, etc.) are considered, if they contain information of direct significance to horticulture. Papers on the technical aspects of horticulture (engineering, crop processing, storage, transport etc.) are accepted for publication only if they relate directly to the living product. In the case of plantation crops, those yielding a product that may be used fresh (e.g. tropical vegetables, citrus, bananas, and other fruits) will be considered, while those papers describing the processing of the product (e.g. rubber, tobacco, and quinine) will not. The scope of the journal includes all horticultural crops but does not include speciality crops such as, medicinal crops or forestry crops, such as bamboo. Basic molecular studies without any direct application in horticulture will not be considered for this journal.