Characterization of key genes in anthocyanin and flavonoid biosynthesis during floral development in Rosa canina L.

This study investigates the transition of Rosa canina L. petals from pink to white, driven by genetic and biochemical factors. It characterizes the expression of ten key genes involved in anthocyanin and flavonoid biosynthesis across five developmental stages, correlating gene expression with flavonoid and anthocyanin concentrations and colorimetric changes. Initially, the petals exhibit a rich flavonoid profile, dominated by Rutin and Kaempferol derivatives. The peak anthocyanin concentration, corresponding to the deepest color saturation, occurs in the subsequent stage. Advanced chromatographic analyses identify key flavonoids persisting into the final white petal stage. Notably, the ANS gene shows a dramatic 137.82-fold increase in expression at the final stage, indicating its crucial role in petal color maturation despite the absence of visible pigmentation. The study provides a comprehensive characterization of the genetic and biochemical mechanisms underlying petal pigmentation, suggesting that reduced anthocyanin synthesis and increased flavonol concentration led to white petals. It also highlights the roles of other genes such as PAL, CCD1, FLS, CHI, CHS, UFGT, F3H, DFR, and RhMYB1, indicating that post-translational modifications and other regulatory mechanisms may influence anthocyanin stability and degradation.

Molecular and Phytochemical Characteristics of Flower Color and Scent Compounds in Dog Rose (Rosa canina L.).

This study delves into the chemical and genetic determinants of petal color and fragrance in Rosa canina L., a wild rose species prized for its pharmacological and cosmetic uses. Comparative analysis of white and dark pink R. canina flowers revealed that the former harbors significantly higher levels of total phenolics (TPC) and flavonoids (TFC), while the latter is distinguished by elevated total anthocyanins (TAC). Essential oils in the petals were predominantly composed of aliphatic hydrocarbons, with phenolic content chiefly constituted by flavonols and anthocyanins. Notably, gene expression analysis showed an upregulation in most genes associated with petal color and scent biosynthesis in white buds compared to dark pink open flowers. However, anthocyanin synthase (ANS) and its regulatory gene RhMYB1 exhibited comparable expression levels across both flower hues. LC-MS profiling identified Rutin, kaempferol, quercetin, and their derivatives as key flavonoid constituents, alongside cyanidin and delphinidin as the primary anthocyanin compounds. The findings suggest a potential feedback inhibition of anthocyanin biosynthesis in white flowers. These insights pave the way for the targeted enhancement of R. canina floral traits through metabolic and genetic engineering strategies.

A comprehensive review of the molecular and genetic mechanisms underlying gum and resin synthesis in Ferula species.

Ferula spp. are plants that produce oleo-gum-resins (OGRs), which are plant exudates with various colors. These OGRs have various industrial applications in pharmacology, perfumery, and food. The main constituents of these OGRs are terpenoids, a diverse group of organic compounds with different structures and functions. The biosynthesis of OGRs in Ferula spp., particularly galbanum, holds considerable economic and ecological importance. However, the molecular and genetic underpinnings of this biosynthetic pathway remain largely enigmatic. This review provides an overview of the current state of knowledge on the biosynthesis of OGRs in Ferula spp., highlighting the major enzymes, genes, and pathways involved in the synthesis of different terpenoid classes, such as monoterpenes, sesquiterpenes, and triterpenes. It also examines the potential of using omics techniques, such as transcriptomics and metabolomics, and genome editing tools, such as CRISPR/Cas, to increase the yield and quality of Ferula OGRs, as well as to create novel bioactive compounds with enhanced properties. Moreover, this review addresses the current challenges and opportunities of applying gene editing in Ferula spp., and suggests some directions for future research and development.

Modulation of Tropane Alkaloids' Biosynthesis and Gene Expression by Methyl Jasmonate in Datura stramonium L.: A Comparative Analysis of Scopolamine, Atropine, and Hyoscyamine Accumulation.

Scopolamine and atropine are two medicinal alkaloids derived from Datura stramonium L. with anticholinergic properties. This study explored how methyl jasmonate (MJ), a plant growth regulator, affects the biosynthesis and accumulation of these alkaloids in different plant tissues. The expression levels of putrescine N-methyltransferase (PMT), tropinone reductase I (TR1), and hyoscyamine 6ß-hydroxylase (h6h), three critical enzymes in the biosynthetic pathway, were also analyzed. The results indicated that MJ at 150 µM increased the production of scopolamine and atropine in both leaves and roots, while MJ at 300 µM had an adverse effect. Furthermore, MJ enhanced the expression of PMT, TR1, and h6h genes in the roots, the primary site of alkaloid synthesis, but not in the leaves, the primary site of alkaloid storage. These results imply that MJ can be applied to regulate the biosynthesis and accumulation of scopolamine and atropine in D. stramonium, thereby improving their production efficiency.

Effect of drought stress on natural rubber biosynthesis and quality in Taraxacum kok-saghyz roots.

Taraxacum kok-saghyz (TKS) is a potential source of natural rubber (NR) that can be grown in temperate regions with limited water availability. However, the effect of drought stress on NR production and properties in TKS isn't well studied. This study examined how different levels of drought stress (30, 60 and 90%) influenced the NR content, molecular weight (Mw), glass transition temperature (Tg), gene expression, and biochemical parameters in TKS roots. The results showed that drought stress didn't significantly change the NR content, but increased the Mw and the expression of CPT and SRPP genes, which are involved in NR biosynthesis. The NR from TKS roots (TNR) had a high Mw of 994,000 g/mol and a low Tg of below -60°C under normal irrigation, indicating its suitability for industrial applications. Drought stress also triggered the accumulation of proline, H2O2, MDA, and antioxidant enzymes (CAT, APX, GPX) in TKS roots significantly, indicating a drought tolerance mechanism. These findings suggest that TKS can produce high-quality NR under drought stress conditions and provide a sustainable alternative to conventional NR sources.