Integration of transcriptome and DNA methylome analysis reveals the molecular mechanism of taproot yield heterosis in radish  

作　　者：Xiaoli Zhang Liang Xu Yan Wang Wei Zhang Xinyu Zhang Junhui Dong Jiali Ying Lun Wang Yinbo Ma Liwang Liu 

机构地区：[1]National Key Laboratory of Crop Genetics&Germplasm Enhancement and Utlization,Key Laboratory of Horticultural Crop Biology and Genetic Improvement(East China)of MOAR,College of Horticulture,Nanjing Agricultural University,Nanjing,Jiangsu 210095,China [2]College of Horticulture and Landscape Architecture,Yangzhou University,Yangzhou,Jiangsu 225009,China

出　　处：《Horticultural Plant Journal》2025年第2期645-660,共16页园艺学报(英文版)

基　　金：supported by grants from the Jiangsu Seed Industry Revitalization Project[Grant No.JBGS(2021)071];Key Technology R&D Program of Jiangsu Province(Grant No.BE2023366);National Natural Science Foundation of China(Grant No.32172579);the earmarked fund for Jiangsu Agricultural Industry Technology System[Grant No.JATS(2023)421];the Fundamental Research Funds for the Central Universities(Grant No.YDZX2023019);the Project Founded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。

摘　　要：Heterosis,a crucial biological phenomenon,plays a vital role in determining the yield and quality of plants.Radish,an important root vegetable crop,exhibits notable heterosis in terms of root yield and quality.Nevertheless,the molecular mechanism underlying the formation of heterosis in radish remains unclear.Herein,both the transcriptome and DNA methylome analyses were performed on the F_(1)hybrids and parental lines.Expression level dominance(ELD)genes and allele-specific expression(ASE)genes together significantly contribute to heterosis,primarily through energy metabolism and plant hormone signal transduction pathway.An increase in average methylation level in the F_(1)hybrids was observed compared to the parental lines.Interestingly,a negative correlation was found between the methylation level of differentially expressed genes(DEGs)in gene body regions and their expression levels in NAU-LB and the F_(1)hybrids.Moreover,the hybrids were more sensitive to the 5-azacytidine than their parents,and the root weight and total sugar content in the F_(1)hybrids were dramatically decreased compared to the control.Immunolocalization results indicated that the auxin content of the F_(1)hybrids were reduced under 5-azacytidine treatment.Proliferating cell nuclear antigen immunolocalization revealed significant inhibition of vascular cambium activity in both the hybrids and parental lines.Notably,the expression profiles of a few differentially methylated DEGs including RsSUS1,RsSUC2a,RsIAA7,and RsIAA18,were significantly increased in the root of hybrids compared to their parents,suggesting a potential role of DNA methylation in yield heterosis.Collectively,these findings would provide valuable insight into the molecular mechanism underlying taproot yield heterosis and facilitate the genetic improvement of taproot yield and quality in radish breeding programs.

关 键 词：Raphanus sativus L. HETEROSIS TRANSCRIPTOME DNA methylation Parental expression level dominance Allele-specific expression 

分 类 号：S631.1[农业科学—蔬菜学]