背景:果实成熟期是果树作物育种计划中的重要目标性状。因此,柑橘树育种者寻求开发极端早熟品种,以优化柑橘的成熟期。在这项研究中,我们使用“纽霍尔脐橙”品种及其早熟突变体探索了参与柑橘果实成熟的调控网络,\'甘南早\'。本研究将为进一步研究重要信号通路提供依据,柑橘果实成熟期相关基因功能及品种选育.
结果:生理分析表明,“甘南灶”的早期果实成熟受脱落酸(ABA)的早期积累调节,茉莉酸(JA)持续高水平,果皮中蔗糖含量较高。在开花后180、200和220天,对来自“Gannanzao”和“Newhall”脐橙的果皮样品进行RNA测序分析;鉴定了1430个差异表达基因(DEG)。功能富集分析表明,这些DEGs主要富集在植物激素信号转导和糖代谢通路,以及其他与果实成熟有关的途径。与“Gannanzao”果实成熟相关的重要DEG包括参与ABA和JA代谢和信号转导的基因,以及糖代谢。加权基因共表达网络分析显示,深粉色模块与ABA含量的相关性最强,JA内容,早熟。基于该模块中37个基因的基因功能和基因表达分析,两个候选hub基因和两个乙烯反应因子13(ERF13)基因(Cs_ont_5g000690和Cs_ont_5g000700)被鉴定为ABA和JA信号调节的关键基因。这些发现将有助于阐明柑橘果实早熟的机制,并将导致开发优良的遗传资源,以进一步选育极端早熟品种。
结论:通过对“纽荷尔”脐橙品种及其早熟突变体“甘南早”的分析,我们确定了与ABA和JA代谢有关的基因,信号转导,以及与果实成熟有关的糖代谢。其中,两个ERF13基因被认为是调控果实成熟的关键基因。这些发现提供了对与中华毛虫早期果实成熟相关的遗传结构的见解。
BACKGROUND: The fruit ripening period is an important target trait in fruit tree crop breeding programs. Thus, citrus tree breeders seek to develop extreme early ripening cultivars that allow optimization of citrus maturation periods. In this study, we explored the regulatory network involved in fruit ripening in Citrus sinensis using the \'Newhall\' navel orange variety and its early-ripening mutant, \'Gannanzao\'. This research will provide a basis for further research on important signaling pathways, gene functions and variety breeding of Citrus sinensis related to fruit ripening period.
RESULTS: Physiological analyses suggested that early fruit ripening in \'Gannanzao\' is regulated by early accumulation of abscisic acid (ABA), persistently high levels of jasmonic acid (JA), and higher sucrose content in the pericarp. Pericarp samples from \'Gannanzao\' and \'Newhall\' navel oranges were sampled for RNA sequencing analysis at 180, 200, and 220 days after flowering; 1430 differentially expressed genes (DEGs) were identified. Functional enrichment analysis indicated that these DEGs were mainly enriched in the plant hormone signal transduction and sugar metabolism pathways, as well as other pathways related to fruit ripening. Important DEGs associated with fruit ripening in \'Gannanzao\' included genes involved in ABA and JA metabolism and signal transduction, as well as sugar metabolism. Weighted gene co-expression network analysis showed that the deep pink module had the strongest correlations with ABA content, JA content, and early ripening. Based on gene functionality and gene expression analyses of 37 genes in this module, two candidate hub genes and two ethylene response factor 13 (ERF13) genes (Cs_ont_5g000690 and Cs_ont_5g000700) were identified as key genes regulated by ABA and JA signaling. These findings will help to clarify the mechanisms that underlie early citrus fruit ripening and will lead to the development of excellent genetic resources for further breeding of extreme early-ripening varieties.
CONCLUSIONS: Through analyses of the \'Newhall\' navel orange cultivar and its early-ripening mutant \'Gannanzao\', we identified genes involved in ABA and JA metabolism, signal transduction, and sugar metabolism that were related to fruit ripening. Among these, two ERF13 genes were inferred to be key genes in the regulation of fruit ripening. These findings provide insights into the genetic architecture related to early fruit ripening in C. sinensis.