香味是水稻品种的重要性状,其香气显著影响消费者的偏好。在这项研究中,我们进行了全面的代谢组和转录组分析,以阐明上思香诺(SSXN)品种中香气的遗传和生化基础,一种在广西种植的香稻,中国。通过感官评价和遗传分析,我们确认SSXN是强烈的芬芳,与香料生产相关的BADH2基因中的806bp缺失。在代谢组分析中,总共238、233、105和60种代谢化合物在幼苗(S)上表现出明显的变化,生殖(R),填充(F),和成熟(M)阶段,分别。我们鉴定了在所有四个发育阶段中表现出SSXN显著变化的四种化合物。我们的分析揭示了2-乙酰基-1-吡咯啉(2AP)的显着上调,经过充分研究的芳香族化合物,在SSXN中与非芳香品种相比。此外,相关性分析确定了几种与2AP强相关的代谢物,包括乙酮,1-(1H-吡咯-2-基)-,1H-吡咯,和吡咯。此外,加权基因共表达网络分析(WGCNA)分析强调了品红色和黄色模块特别富含香气相关代谢物,提供对大米香气背后复杂的芳香化合物的见解。在转录组分析中,在四个发育阶段共鉴定了5582、5506、4965和4599个差异表达基因(DEG),在所有阶段都显着富集了常见的途径氨基糖和核苷酸糖代谢。在代谢组和转录组数据的相关性分析中,前三个相连的代谢物,苯酚-,3-氨基-,2AP,还有乙酮,1-(1H-吡咯-2-基)-,表现出与成绩单的强烈关联,强调它们在香料生物合成中的潜在作用。此外,P4H4基因表达下调,编码特异性靶向脯氨酸的前胶原-脯氨酸双加氧酶,在SSXN中表明其参与脯氨酸代谢和潜在的香气形成途径。总的来说,我们的研究提供了对水稻香气产生的遗传和生化机制的全面见解,为进一步研究旨在提高水稻育种计划中的香气品质奠定了基础。
Fragrance is a valuable trait in rice varieties, with its aroma significantly influencing consumer preference. In this study, we conducted comprehensive metabolome and transcriptome analyses to elucidate the genetic and biochemical basis of fragrance in the Shangsixiangnuo (SSXN) variety, a fragrant indica rice cultivated in Guangxi,
China. Through sensory evaluation and genetic analysis, we confirmed SSXN as strongly fragrant, with an 806 bp deletion in the BADH2 gene associated with fragrance production. In the metabolome analysis, a total of 238, 233, 105 and 60 metabolic compounds exhibited significant changes at the seedling (S), reproductive (R), filling (F), and maturation (M) stages, respectively. We identified four compounds that exhibited significant changes in SSXN across all four development stages. Our analyses revealed a significant upregulation of 2-acetyl-1-pyrroline (2AP), the well-studied aromatic compound, in SSXN compared to the non-fragrant variety. Additionally, correlation analysis identified several metabolites strongly associated with 2AP, including ethanone, 1-(1H-pyrrol-2-yl)-, 1H-pyrrole, and pyrrole. Furthermore, Weighted Gene Co-expression Network Analysis (WGCNA) analysis highlighted the magenta and yellow modules as particularly enriched in aroma-related metabolites, providing insights into the complex aromatic compounds underlying the fragrance of rice. In the transcriptome analysis, a total of 5582, 5506, 4965, and 4599 differential expressed genes (DEGs) were identified across the four developmental stages, with a notable enrichment of the common pathway amino sugar and nucleotide sugar metabolism in all stages. In our correlation analysis between metabolome and transcriptome data, the top three connected metabolites, phenol-, 3-amino-, and 2AP, along with ethanone, 1-(1H-pyrrol-2-yl)-, exhibited strong associations with transcripts, highlighting their potential roles in fragrance biosynthesis. Additionally, the downregulated expression of the P4H4 gene, encoding a procollagen-proline dioxygenase that specifically targets proline, in SSXN suggests its involvement in proline metabolism and potentially in aroma formation pathways. Overall, our study provides comprehensive insights into the genetic and biochemical mechanisms underlying fragrance production in rice, laying the foundation for further research aimed at enhancing fragrance quality in rice breeding programs.