Li Jieni, Tan Quanya, Yi Maosheng, Yu Zhengnan, Xia Qing, Zheng Lu, Chen Jianjun, Zhou Xiaoyun, Zhang Xiang-Qian, Guo He-Rong
College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China.
Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China.
Front Plant Sci. 2023 Sep 6;14:1208226. doi: 10.3389/fpls.2023.1208226. eCollection 2023.
Modern anthuriums, (Hort.) are among the most popular flowering plants and widely used for interior decoration. Their popularity is largely attributed to the exotic spathes with different colors. Previous studies have reported color development in red spathe cultivars, but limited information is available on key genes regulating white and green colored spathes. This study analyzed anthocyanin, chlorophyll, and carotenoid contents as well as transcript differences in spathes of eight cultivars that differed in spathe colors ranging from red to white and green. Results showed that increased expression of a transcription factor was associated with elevated levels of anthocyanin in spathes, but decreased expression of and increased expression of (leucoanthocyanidin reductase) and (anthocyanidin reductase) were accompanied with the accumulation of colorless proanthocyanidin, thus the white spathe. As to the green colored spathe, chlorophyll content in the green spathe cultivar was substantially higher than the other cultivars. Correspondingly, transcripts of chlorophyll biosynthesis-related genes (porphobilinogen synthase) and (protochlorophyllide oxidoreductase) were highly upregulated but almost undetectable in white and red spathes. The increased expression of and was correlated with the expression of transcription factor . Subsequently, qRT-PCR analysis confirmed their expression levels in nine additional cultivars with red, white, and green spathes. A working model for the formation of white and green spathes was proposed. White colored spathes are likely due to the decreased expression of which results in increased expression of and , and the green spathes are attributed to enhanced expression of and . Further research is warranted to test this working model.
现代花烛属植物（Hort.）是最受欢迎的开花植物之一，广泛用于室内装饰。它们的受欢迎程度很大程度上归因于具有不同颜色的奇异佛焰苞。先前的研究报道了红色佛焰苞品种的颜色发育，但关于调控白色和绿色佛焰苞的关键基因的信息有限。本研究分析了8个佛焰苞颜色从红色到白色和绿色的品种的佛焰苞中的花青素、叶绿素和类胡萝卜素含量以及转录差异。结果表明，一种转录因子的表达增加与佛焰苞中花青素水平的升高有关，但另一种转录因子的表达降低以及无色花青素还原酶和花青素还原酶的表达增加伴随着无色原花青素的积累，从而形成白色佛焰苞。对于绿色佛焰苞，绿色佛焰苞品种中的叶绿素含量明显高于其他品种。相应地，叶绿素生物合成相关基因（胆色素原合酶）和（原叶绿素酸酯氧化还原酶）的转录本在绿色佛焰苞中高度上调，但在白色和红色佛焰苞中几乎检测不到。这两种基因的表达增加与转录因子的表达相关。随后，qRT-PCR分析证实了它们在另外9个具有红色、白色和绿色佛焰苞的品种中的表达水平。提出了白色和绿色佛焰苞形成的工作模型。白色佛焰苞可能是由于某种转录因子表达降低导致无色花青素还原酶和花青素还原酶表达增加所致，而绿色佛焰苞则归因于这两种基因的表达增强。有必要进行进一步的研究来验证这个工作模型。
