首页分享高质量毛花猕猴桃基因组为抗坏血酸调控机制研究提供新见解

高质量毛花猕猴桃基因组为抗坏血酸调控机制研究提供新见解

来源：花匠小妙招时间：2024-12-06 14:09

摘要：

毛花猕猴桃是猕猴桃属中果实抗坏血酸(AsA)含量较高的种之一，但其果实富含抗坏血酸的分子机制尚未被解析。为了深入探明毛花猕猴桃果实富含AsA的分子机制，本研究通过结合基因组学、代谢组学和转录组学构建了AsA代谢相关的调控网络，从而为后续研究奠定基础。在本研究中，我们组装了一个仅含有5个缺口的高质量毛花猕猴桃参考基因组。该基因组由29条染色体组成，大小为615.95 Mb, contig N50为20.35 Mb，其中24条染色体直接来自端粒到端粒。基因组组装评价指标LAI值和QV值分别为21.34%和39.90%，表明组装的基因组已经达到了金标准参考基因组水平。随后，通过代谢组和转录组分析，分别发现61个代谢物和2,092个基因在果实生长发育过程中存在差异积累/表达。在所有的AsA代谢途径中，AsA降解和循环再生途径在整个果实生长发育过程中显著性高表达，表明该途径在AsA调控中起着重要作用。此外，AsA含量与抗坏血酸过氧化物酶基因高度相关。本研究组装的高质量毛花猕猴桃基因组将为毛花猕猴桃遗传育种研究提供坚实的基础，构建的调控网络将为今后毛花猕猴桃的基因功能研究提供公共数据平台。

Abstract:

Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content. However, the molecular mechanism driving AsA richness in fruit remains unclear. In order to reveal the molecular mechanism of AsA richness in A. eriantha, this study constructed a regulatory network related to AsA metabolism by combining genomics, metabolomics and transcriptomics. We assembled a high-quality genome of A. eriantha ‘Ganlv 1’ with only five remaining gaps. The assembly is comprised of 29 pseudochromosomes with a total size of 615.95 Mb, and contig N50 of 20.35 Mb. Among them, 24 of the pseudochromosomes were obtained directly from telomere-to-telomere. The LTR assembly index score and consensus quality value were 21.34 and 39.90%, respectively. Subsequently, 61 metabolites and 2 092 genes were found to be differentially accumulated/expressed during fruit development by metabolome and transcriptome assays, respectively. AsA metabolism and the cyclic regeneration pathway were found to have high expression levels throughout fruit growth and development, suggesting its crucial role in the regulation of AsA. Furthermore, the AsA contents are highly associated with ascorbate peroxidase genes. The genome obtained in this study provides genomic resources for the genetic and breeding research of A. eriantha, and the constructed regulatory network can provide a public data platform for future research on kiwifruit.

Key words: Actinidia eriantha , scorbic acid , non-targeted metabolome , gapless genome , transcriptome