Unlocking the color secrets of water lilies: gene study reveals what makes petals blue, red, or white

Researchers identified 32 anthocyanin synthase (ANS) genes in the water lily species Nymphaea colorata and analyzed their structure, evolutionary history, and expression patterns. The study found that certain ANS genes were highly expressed in blue and red petals, while showing low activity in white flowers, directly linking gene expression with pigment production.

Anthocyanins, water-soluble pigments in the flavonoid family, give rise to the vivid red, purple, and blue hues in many plants. These pigments serve ecological functions such as attracting pollinators and protecting against environmental stress. Nymphaea (water lilies) are ancient flowering plants that exhibit a striking diversity of petal colors, making them ideal models for color evolution and genetic studies. Previous research has highlighted anthocyanins’ central role in floral coloration, but the specific regulatory genes responsible in N. colorata remain underexplored. Due to these knowledge gaps, a detailed investigation of the ANS gene family in this species is essential for understanding the molecular basis of flower color variation.

A study (DOI: 10.48130/tp-0025-0006) published in Tropical Plants on 24 March 2025 by Yang Bai & Fei Chen’s team, Hainan University, not only deepens our understanding of flower coloration in aquatic plants but also provides a foundation for targeted breeding of ornamental plants with customized petal hues.

To investigate the genetic underpinnings of flower color variation in Nymphaea colorata, researchers conducted a comprehensive analysis of the ANS gene family using genomic, phylogenetic, structural, and expression profiling methods. Initially, 32 NcANS genes were identified from the N. colorata genome and characterized based on their chromosomal positions and physicochemical features. These genes exhibited considerable variation in protein length, molecular weight, isoelectric points, and stability, with most predicted to be hydrophilic and functionally unstable—indicating diverse roles in cellular processes. Phylogenetic analysis incorporating ANS genes from six other plant species grouped the NcANS genes into seven subfamilies, highlighting both conserved and lineage-specific evolution. Motif and domain analyses revealed shared structural features such as the 2OG-FE(II)-dependent oxygenase and Diox domains, essential for anthocyanin biosynthesis. Promoter analysis uncovered a wide range of regulatory elements, including light- and hormone-responsive motifs, suggesting external stimuli may influence gene activity. Synteny and collinearity assessments revealed five syntenic gene pairs within N. colorata and multiple homologous genes shared with other dicotyledonous species, implying evolutionary conservation. Selection pressure analysis confirmed that the NcANS gene family has undergone purifying selection. Finally, transcriptome data and qPCR validation showed that several NcANS genes—including NcANS15, NcANS16, and NcANS19—were highly expressed in red and blue petals but nearly silent in white flowers. This expression pattern corresponded with measured anthocyanin content and underscores the critical role of specific NcANS genes in determining petal pigmentation. These findings collectively reveal that flower color in N. colorata is genetically regulated through a complex and evolutionarily conserved network of ANS genes, providing a foundational resource for future studies in molecular breeding and floral trait manipulation.

These findings provide critical groundwork for developing genetically customized water lily varieties with enhanced color traits through molecular breeding. The study also opens avenues for exploring how environmental cues like light and temperature influence pigment biosynthesis via hormonal and promoter-level regulation. Moreover, dynamic expression profiling across floral development stages will help elucidate temporal gene regulation patterns. Understanding ANS gene networks could ultimately contribute to broader applications in horticulture, agriculture, and ecological adaptation studies.

###

References

DOI

10.48130/tp-0025-0006

Original Source URL

https://doi.org/10.48130/tp-0025-0006

Funding information

This work was supported by the National Natural Science Foundation of China (32172614), and Hainan Provincial Natural Science Foundation of China (324RC452).

About Tropical Plants

Tropical Plants (e-ISSN 2833-9851) is the official journal of Hainan University and published by Maximum Academic Press. Tropical Plants undergoes rigorous peer review and is published in open-access format to enable swift dissemination of research findings, facilitate exchange of academic knowledge and encourage academic discourse on innovative technologies and issues emerging in tropical plant research.