Anthocyanin biosynthesis in plants is spatiotemporally controlled by a suite of transcription factors, with MYB proteins playing a key regulatory role. However, the evolution of the distinct roles of MYB paralogs remains poorly understood. Our previous studies have established GmMYBA2 and GmMYBA3 as the regulators of seed coat and floral anthocyanin production in soybean (Glycine max), respectively. In this study, we reveal the functional divergence of their paralog GmMYBA1 in orchestrating light-responsive anthocyanin biosynthesis in juvenile tissues and stems. In brief, hypocotyl/stem- and young leaf-predominant expression of GmMYBA1 correlates with photoprotective anthocyanin accumulation. Ectopic overexpression of GmMYBA1 induces systemic pigmentation across leaves, stems, and reproductive organs, whereas RNAi-mediated silencing of GmMYBA1 significantly reduces anthocyanin accumulation in the hypocotyl. Light-dark shift assays confirmed that GmMYBA1 is required for hypocotyl pigmentation, while dual-luciferase assays revealed the specific regulation of the GmMYBA paralogs by GmSTF1/2 (soybean TGACG-motif binding factor 1/2). GmSTF1/2 both activate GmMYBA1, with only GmSTF2 weakly inducing GmMYBA2 and neither affecting GmMYBA3. Further investigation indicated that the differential transactivation of GmMYBA promoters largely resulted from their cis-element difference, suggesting regulatory divergence as a driver of MYB paralog diversification. Our findings position GmMYBA1 as the central MYB activator integrating light signaling with anthocyanin biosynthesis, with paralog specialization reflecting evolutionary subfunctionalization post-gene duplication.

Anthocyanins play crucial roles in pollen protection and pollinator attraction in flowering plants. However, the mechanisms underlying flower color determination and whether floral anthocyanin regulators participate in other processes remain largely unresolved in soybeans (Glycine max). In this study, we investigated the genetic components and mechanisms governing anthocyanin biosynthesis in soybean flowers. Molecular and genetic studies have characterized two antagonistic regulators, the positive activator GmMYBA3 and the negative repressor GmMYBR1, that modulate the gene expression of anthocyanin biosynthesis in soybean flowers. Further findings revealed a regulatory interplay between GmMYBA3 and GmMYBR1 bridged by GmTT8a, highlighting the complexity of anthocyanin regulation in different soybean organs. Exploration of additional soybean cultivars demonstrated the universality of GmMYBA3 and GmMYBR1 in regulating floral anthocyanin biosynthesis- related genes, with GmF3′5′H identified as a crucial determinant of white flower color. This study provides a molecular mechanism underlying soybean flower color determination, paving the way for the molecular modification of soybean flowers to probably enhance their resistance to abiotic stresses and attractiveness to pollinators.

Floral color and scent are crucial for plant–environment interactions, especially in reproduction by attracting pollinators for fertilization. They also have wide applications in cosmetic, pharmaceutical, and nutraceutical industries. Plant pigments are typically classified as chlorophylls, flavonoids, carotenoids, and betalains, while volatile organic compounds (VOCs) are grouped as terpenes, phenylpropanoids/benzenoids, and fatty acid derivatives. Significant progresses have been made in understanding the biosynthesis and regulation of these floral pigments and VOCs. Despite differences in their biosynthetic pathways, floral pigments and VOCs are biochemically connected and exhibit synergistic interactions during flower development and in response to biotic and abiotic stresses, suggesting the existence of pleiotropic regulators or complex mechanisms co-regulating their biosynthesis. In this review, we summarize and outline the metabolite pathways mainly integrating flavonoids, carotenoids, terpenes, and phenylpropanoids/benzenoids. We also provide a series of scenarios illustrating the coordinated regulation of floral color and scent. Finally, we suggest areas for future research. We hope this review will spark interest in this research direction and stimulate further studies.

Candida albicans (C. albicans) infection has a high mortality rate in immunocompromised patients. Owing to the inefficiency of the current diagnostic system and the absence of licensed vaccines against candidiasis, the prevention of C. albicans infection remains a challenge. C. albicans infection can be evaluated and prevented by the anti-secreted aspartyl proteinase 2 antibody (anti-Sap2 IgG) and Hsp90 antibody (anti-Hsp90 IgG). In this study, to explore a new agent for the improvement of the diagnosis and the prevention of C. albicans infection, an engineered fd bacteriophage, which is considered a human-safe virus nanofiber, was designed and prepared with two epitopes that could induce and capture anti-Sap2 IgG and anti-Hsp90 IgG. The dual-display phage was employed as a novel capture probe to develop a new enzyme-linked immunosorbent assay (ELISA) method, which significantly improved the detection rate compared with those of the ELISA in which recombinant protein Sap2 was used as coating antigen to capture the specific antibodies (rSap2-ELISA) and the ELISA in which recombinant protein Hsp90 was used as coating antigen to capture the specific antibodies (rHsp90-ELISA). In addition, the nanofibers acted as a potential vaccine to immunize mice, as well as recombinant proteins, more efficiently mediated humoral and cellular immune responses, decreased levels of C. albicans colonization, and increased the survival rates in C. albicans-infected mice. Therefore, the phage dual-display nanofiber has been shown to be a powerful bifunctional agent for protection against and sensitive detection of clinical infections, which has the potential to be widely used in the life sciences, clinical medicine, and environmental sciences.