Institute of Pomology and Olericulture, College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China.
Int J Mol Sci. 2022 May 22;23(10):5808. doi: 10.3390/ijms23105808.
is one of the very few kiwifruit genotypes with extremely high ascorbic acid (AsA) content. However, a transcriptome atlas of this species is lacking. The accumulation of AsA during fruit development and ripening and the associated molecular mechanisms are still poorly understood. Herein, dynamic changes in AsA content at six different stages of fruit development and ripening were determined. AsA content of fruit reached 1108.76 ± 35.26 mg 100 g FW at full maturity. A high-quality, full-length (FL) transcriptome of was successfully constructed for the first time using third-generation sequencing technology. The transcriptome comprises 326,926 FL non-chimeric reads, 15,505 coding sequences, 2882 transcription factors, 18,797 simple sequence repeats, 3328 long noncoding RNAs, and 231 alternative splicing events. The genes involved in AsA biosynthesis and recycling pathways were identified and compared with those in different kiwifruit genotypes. The correlation between the AsA content and expression levels of key genes in AsA biosynthesis and recycling pathways was revealed. LncRNAs that participate in AsA-related gene expression regulation were also identified. Gene expression patterns in AsA biosynthesis and metabolism exhibited a trend similar to that of AsA accumulation. Overall, this study paves the way for genetic engineering to develop kiwifruits with super-high AsA content.
是极少数具有极高抗坏血酸（AsA）含量的猕猴桃基因型之一。然而，该物种的转录组图谱仍然缺乏。AsA 在果实发育和成熟过程中的积累及其相关的分子机制仍知之甚少。在此，我们确定了 果实发育和成熟的六个不同阶段 AsA 含量的动态变化。果实完全成熟时，AsA 含量达到 1108.76±35.26mg 100gFW。首次使用第三代测序技术成功构建了 的高质量全长（FL）转录组。该转录组包含 326926 条 FL 非嵌合reads，15505 个编码序列，2882 个转录因子，18797 个简单序列重复，3328 个长非编码 RNA 和 231 个选择性剪接事件。鉴定了参与 AsA 生物合成和循环途径的基因，并与不同猕猴桃基因型中的基因进行了比较。揭示了 AsA 生物合成和循环途径中关键基因的表达水平与 AsA 含量之间的相关性。还鉴定了参与 AsA 相关基因表达调控的 lncRNA。AsA 生物合成和代谢中的基因表达模式与 AsA 积累的趋势相似。总的来说，这项研究为开发具有超高 AsA 含量的猕猴桃的基因工程铺平了道路。
