Ma Li, Ding Suqin, Fu Xueqing, Yan Zi, Tang Dongqin
Department of Landscape Architecture, Shanghai Jiao Tong University, Shanghai, China.
Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
PeerJ. 2021 Mar 19;9:e11078. doi: 10.7717/peerj.11078. eCollection 2021.
Starch and sucrose metabolism plays a crucial role in the formation and development of bulbs in bulbous plants. However, these mechanisms remain unclear and unexplored in the corms of . Herein, we investigated the dynamics of the major form of carbohydrates and related enzyme activities and profiled the transcriptome of freesia corms at four developmental stages with the aim to reveal the relation between the expression of genes involved in the metabolism of carbohydrates and the accumulation of carbohydrates in corm developmental stages for further exploring the mechanism on the starch and sucrose metabolism regulating the formation and development of corms in . The content of starch, sucrose and soluble sugars followed an overall upward trend across the corm developmental stages. Activities of the adenosine diphosphoglucose pyrophosphorylase, starch branching enzyme and β-amylase generally followed the pattern of the starch and sucrose levels. Activities of sucrose phosphate synthase increased from corm formation till the initial swelling stage and subsequently reached a plateau. Activities of invertase and sucrose synthase peaked at the later rapid swelling stage. These suggested that the starch and sucrose dynamics paralleled corm swelling under the action of metabolic enzymes. A total of 100,999 unigenes were assembled in the transcriptomic analysis, and 44,405 unigenes of them were annotated. Analysis based on Clusters of Orthologous Groups suggested that carbohydrate transport and metabolism (9.34% of the sequences) was prominent across the corm developmental process. In total 3,427 differentially expressed genes (DEGs) were identified and the enrichment analysis detected starch and sucrose metabolism as a critical pathway in corm development, especially at the rapid swelling stage. Further, DEGs encoding key carbohydrate-metabolizing enzymes were identified and correlated to enzyme activities and carbohydrate accumulation. The results construct a valuable resource pool for further molecular-level studies, which are helpful for metabolic regulation of carbohydrates and improvement in .
淀粉和蔗糖代谢在球根植物鳞茎的形成和发育过程中起着关键作用。然而，这些机制在[植物名称]的球茎中仍不清楚且未被探索。在此，我们研究了碳水化合物主要形式的动态变化以及相关酶活性，并分析了小苍兰球茎在四个发育阶段的转录组，旨在揭示碳水化合物代谢相关基因的表达与球茎发育阶段碳水化合物积累之间的关系，以便进一步探索淀粉和蔗糖代谢调节[植物名称]球茎形成和发育的机制。在整个球茎发育阶段，淀粉、蔗糖和可溶性糖的含量总体呈上升趋势。腺苷二磷酸葡萄糖焦磷酸化酶、淀粉分支酶和β -淀粉酶的活性通常与淀粉和蔗糖水平的变化模式一致。蔗糖磷酸合成酶的活性从球茎形成期到初始膨大期增加，随后达到稳定水平。转化酶和蔗糖合成酶的活性在后期快速膨大期达到峰值。这些结果表明，在代谢酶的作用下，淀粉和蔗糖的动态变化与球茎膨大过程平行。转录组分析共组装得到100,999个单基因，其中44,405个单基因得到注释。基于直系同源簇的分析表明，碳水化合物运输和代谢（占序列的9.34%）在整个球茎发育过程中较为突出。总共鉴定出3427个差异表达基因（DEGs），富集分析检测到淀粉和蔗糖代谢是球茎发育中的关键途径，尤其是在快速膨大期。此外，还鉴定出了编码关键碳水化合物代谢酶的DEGs，并将其与酶活性和碳水化合物积累相关联。这些结果构建了一个有价值的资源库，有助于进一步的分子水平研究，对碳水化合物的代谢调控和[植物名称]的改良具有重要意义。
