Ou Zhi, Luo Jun, Qu Yan
Southwest Engineering and Technology Research Center of Landscape Architecture (National Forestry and Grassland Administration), Yunnan Engineering Research Center for Functional Flower Resources and Industrialization, Southwest Forestry University, Kunming, Yunnan, 650224, China.
Southwest Engineering and Technology Research Center of Landscape Architecture (National Forestry and Grassland Administration), Yunnan Engineering Research Center for Functional Flower Resources and Industrialization, Southwest Forestry University, Kunming, Yunnan, 650224, China.
Dev Biol. 2024 Jan;505:1-10. doi: 10.1016/j.ydbio.2023.10.003. Epub 2023 Oct 12.
Flower color diversity is a key taxonomic trait in Meconopsis species, enhancing their appeal as ornamental flowers. However, knowledge of the molecular mechanisms of flower color formation in Meconopsis species is still limited. M. wilsonii subsp. australis (Australis) and M. wilsonii subsp. orientalis (Orientalis) have a developmental stage presenting red-purple flowers, while Orientalis also presents blue coloration at the full-bloom period, making them an important model for exploring the mechanism of blue flower formation in M. wilsonii. In this study, we collected petals from Australis and Orientalis at different developmental stages to compare the coloration differences between the two species and detect the molecular mechanisms of blue color in Orientalis. We identified that cyanidin was the main anthocyanin in the flowers of both species, and the blue color in Orientalis primarily arises from anthocyanins (Cyanidin-3-O-sambubioside). RNA sequencing analysis was performed to detect the gene expression in the anthocyanin biosynthesis pathway, and the results suggested that gene regulation for anthocyanin biosynthesis may not be the direct reason for blue color formation in Orientalis. In addition, the growth solid of Orientalis was rich in Fe and Mg ions, and a large amount of Fe and Mg ions accumulated in the petals of Orientalis. Combined with the gene functional enrichment results, we found that the purple and red-purple colors of these two species were presented by different glycosylation levels of cyanidin, while the violet color of Orientalis might be the results of metalloanthocyanins by Fe and Mg ions, which also relieved the toxicity caused by the high content of Fe and Mg ions in its cells. The environmental adaptation-related genes were highly expressed of in both species, such as adaptation to desiccation, water deprivation, freezing, etc. Our results revealed the coloration differences between Australis and Orientalis and described the molecular mechanisms of blue coloration in Orientalis. The data in our analysis could enrich the genetic resources for M. wilsonii for further studies.
花色多样性是绿绒蒿属植物的一个关键分类学特征，增强了它们作为观赏花卉的吸引力。然而，关于绿绒蒿属植物花色形成的分子机制的知识仍然有限。川西绿绒蒿亚种南方绿绒蒿（Australis）和川西绿绒蒿亚种东方绿绒蒿（Orientalis）有一个发育阶段呈现红紫色花朵，而东方绿绒蒿在盛花期还呈现蓝色，这使它们成为探索川西绿绒蒿蓝色花形成机制的重要模型。在本研究中，我们收集了南方绿绒蒿和东方绿绒蒿不同发育阶段的花瓣，以比较这两个物种之间的颜色差异，并检测东方绿绒蒿蓝色的分子机制。我们确定矢车菊素是这两个物种花朵中的主要花青素，东方绿绒蒿中的蓝色主要源于花青素（矢车菊素-3-O-接骨木二糖苷）。进行了RNA测序分析以检测花青素生物合成途径中的基因表达，结果表明花青素生物合成的基因调控可能不是东方绿绒蒿蓝色形成的直接原因。此外，东方绿绒蒿的生长基质富含铁和镁离子，大量的铁和镁离子在东方绿绒蒿的花瓣中积累。结合基因功能富集结果，我们发现这两个物种的紫色和红紫色是由矢车菊素不同的糖基化水平呈现的，而东方绿绒蒿的紫色可能是铁和镁离子形成金属花青素的结果，这也缓解了其细胞中铁和镁离子高含量所造成的毒性。这两个物种中与环境适应相关的基因都高度表达，例如对干燥、缺水、冷冻等的适应。我们的结果揭示了南方绿绒蒿和东方绿绒蒿之间的颜色差异，并描述了东方绿绒蒿蓝色形成的分子机制。我们分析中的数据可以丰富川西绿绒蒿的遗传资源以供进一步研究。
