The WD40 gene family is a highly conserved protein family in plants that plays a crucial role in various life activities. Although eggplant (Solanum melongena L.) genome sequencing has been completed, there is limited research on the WD40 family in eggplant, and the regulatory mechanism of its involvement in anthocyanin synthesis remains poorly understood. The research identified the eggplant WD40 gene family, comprising 187 SmWD40 members that are unevenly distributed across 12 chromosomes of the eggplant. Phylogenetic analysis classified them into 11 subgroups, with members within the same subgroup having similar motifs and gene structures. The promoter of the SmWD40 genes contains a high number of light, stress, and hormone response elements. The expression patterns of 20 SmWD40 members of the S5 subgroup were analyzed during the formation of fruit color in long purple eggplant. Subsequently, we used virus-induced gene silencing (VIGS) to confirm the significance of the TTG1 (SmWD40-56) gene in subgroup S5 for anthocyanin synthesis in eggplant fruit. To investigate the molecular mechanism of SmWD40-56 in eggplant fruit color formation, we analyzed the expression patterns of structural genes for anthocyanin synthesis in eggplant fruit silenced for SmWD40-56. Finally, we predicted the protein interaction network of the SmWD40-56 gene to understand its potential regulatory mechanisms. The result showed that SmWD40-56 may regulate the structural genes involved in anthocyanin biosynthesis and plays an important role in eggplant fruit color formation. This study provides some basis for studying the mechanism of eggplant fruit color formation.

Capsicum frutescens is a valuable economic crop that is widely cultivated for its unique flavor and rich nutritional content. While some studies have shown differences in flavonoid content among different chili species, the mechanism by which changes in flavonoid composition lead to fruit color variations in C. frutescens remains underreported. We performed transcriptomics and widely targeted metabolome sequencing on three different growth stages of the C. frutescens fruit and analyzed the data to better understand the mechanism of color change. Based on previous research on the genes that regulate flavonoid compounds and the MBW complex, we have identified a total of 28 core genes related to flavonoid biosynthesis and 8 genes that may be related to flavonoid synthesis. Through extensive targeted metabolomic analysis, 581 differential metabolites were identified, including 43 flavonoids. Most anthocyanins, flavonols, and flavonoids were found to be more abundant during the immature fruit stage, which we presume is associated with the differential expression of genes involved in flavonoid biosynthesis and regulation. These findings provide a useful reference for understanding flavonoid synthesis and the accumulation of fruits in C. frutescens.

As a great economic Solanum with ornamental value and good adaptability, Solanum aculeatissimum is considered an excellent candidate for the phytoremediation of Cadmium-contaminated soils. However, there are no studies on the involvement of S. aculeatissimum in the response and tolerance mechanisms of cadmium (Cd) stress. In the present study, S. aculeatissimum was used for the first time for physiological and transcriptomic systematic analysis under different concentrations of Cd stress. The results showed that S. aculeatissimum was indeed well tolerant to Cd and showed Cd enrichment capabilities. Under the Cd stress treatment of 50 mg/kg (Cd6), S. aculeatissimum could still grow normally. At the 90th day of Cd stress, the amount of Cd content in different parts of the plant at the same concentration was in the order of root > stem > leaf. With the extension of the stress time up to 163 d, the trend of Cd content in each part was not consistent, and the results in the root (77.74 mg/kg), stem (30.01 mg/kg), leaf (29.44 mg/kg), immature fruit (18.36 mg/kg), and mature fruit (21.13 mg/kg) of Cd peaked at Cd4, Cd5, Cd1, Cd4, and Cd4, respectively. The enrichment and transport coefficients of all treatments were greater than 1. The treatment groups with the largest and smallest enrichment coefficients were Cd4 and CK, respectively. The treatment groups with the largest and smallest transport coefficients were CK and Cd4, respectively. Malondialdehyde (MDA), peroxidase (POD), and catalase (CAT) in the antioxidant system after Cd stress treatment were significantly increased compared to the untreated group. Under cadmium stress, by using real-time quantitative PCR, four genes (SaHMA20, SaL-AO, SaPrxs4, and SaPCs) were screened for possible correlations to Cd tolerance and absorption enrichment in S. aculeatissimum. The key DEGs are mainly responsible for the metabolic pathways of heavy metal ATPases, plastocyanin protein phytocyanins (PCs), peroxidases (Prxs), and ascorbate oxidase (AAO); these differential genes are believed to play an important role in Cd tolerance and absorption enrichment in S. aculeatissimum.

The MYB transcription factors (TFs) have substantial functions in anthocyanin synthesis as well as being widely associated with plant responses to various adversities. In the present investigation, we found an unreported MYB TF from Solanum aculeatissimum (a wild relative of eggplant) and named it SaMYB113 in reference to its homologous gene. Bioinformatics analysis demonstrated that the open reading frame of SaMYB113 was 825 bp in length, encoding 275 amino acids, with a typical R2R3-MYB gene structure, and predicted subcellular localization in the nucleus. Analysis of the tissue-specific expression pattern through qRT-PCR showed that the SaMYB113 was expressed at a high level in young stems as well as leaves of S. aculeatissimum. Transgenic Arabidopsis and tobacco plants overexpressing SaMYB113 pertinent to the control of the 35S promoter exhibited a distinct purple color trait, suggesting a significant change in their anthocyanin content. Furthermore, we obtained three tobacco transgenic lines with significant differences in anthocyanin accumulation and analyzed the differences in anthocyanin content by LC-MS/MS. The findings demonstrated that overexpression of SaMYB113 caused tobacco to have considerably raised levels of several anthocyanin components, with the most significant increases in delphinidin-like anthocyanins and cyanidin-like anthocyanins. The qRT-PCR findings revealed significant differences in the expression levels of structural genes for anthocyanin synthesis among various transgenic lines. In summary, this study demonstrated that the SaMYB113 gene has a substantial impact on anthocyanin synthesis, and overexpression of the SaMYB113 gene leads to significant modifications to the expression levels of a variety of anthocyanin-synthesizing genes, which leads to complex changes in anthocyanin content and affects plant phenotypes. This present research offers the molecular foundation for the research of the mechanism of anthocyanin formation within plants, as well as providing some reference for the improvement of traits in solanum crops.

Introduction: Solanum nigrum , a member of the Solanaceae family, holds significant importance in various aspects, including edible and medicinal uses, ecological management, and environmental landscaping. The leaf edges of S. nigrum exhibit 4–5 significant serrations, and the splitting of these leaf margins plays a crucial role in the plant’s adaptation to environmental shifts. Methods: In this study, we systematically analyzed the molecular mechanism of leaf margin fission in S. nigrum by combining RNA sequencing, weighted gene co-expression network analysis, and overexpression transgenic technology using leaves from five growth stages of S. nigrum during the flowering period as materials. Results: Transcriptome analysis revealed that 30,311 differentially expressed genes were activated from leaf bud to mature leaf, and these genes were significantly enriched in metabolic pathways related to signal transduction and glycosynthesis. Differential genes were hierarchically clustered into 13 modules. The correlations of these modules with different growth stages of S. nigrum leaves, as well as the number and depth of leaf notches were analyzed. It was found that the turquoise expression module (ME1) was significantly and positively correlated with the leaf bud stage (r = 0.94, p < 0.01), while negatively correlated with the number and depth of leaf notches. Three highly connected hub genes were identified from network interactions analysis of genes related to the leaf differentiation pathway in Module 1. From the intersection of the turquoise module and the 2 clusters screened by temporal analysis, the core gene ( SnNAC90 ) for leaf margin fission in lobelia was identified. The regulatory role of the SnNAC90 gene in tobacco leaves was preliminarily verified by transgenic technology. Discussion: It was hypothesized that it might positively regulate leaf margin fission in S. nigrum . Preliminary speculation on its regulatory role in S. nigrum leaves. This study, for the first time, revealed the regulatory mechanism of leaf margin division in S. nigrum , providing a theoretical basis for enriching its germplasm resources and serving as a reference basis for cultivating leaf plants.

Centella asiatica (L.) Urb., a perennial herb of the Apiaceae family, is an important medicinal plant with diverse therapeutic applications. In this study, we integrated phenotypic evaluation, SSR markers, and HPLC fingerprinting to assess the diversity of 24 C. asiatica accessions collected from Yunnan Province, China. Considerable phenotypic, genetic, and biochemical diversity was observed. The Shannon–Wiener index ranged from 2.20 to 3.14 for qualitative traits. Principal component analysis identified five components accounting for 82.54% of the total phenotypic variance, with leaf morphology as the primary determinant. Q-type cluster analysis grouped the accessions into five phenotypic clusters. Transcriptome analysis revealed 16,799 SSR loci, with dinucleotide repeats as the most frequent motif (44.31%). UPGMA clustering based on SSR markers delineated five genetic groups that correlated with geographic origin, with accessions from the two northernmost sites forming a distinct cluster. HPLC fingerprints identified 16 common peaks, among which five major bioactive constituents—madecassoside, asiaticoside, kaempferol, madecassic acid, and asiatic acid—were quantified. The total content of these five compounds varied markedly among accessions (4.09–20.18 mg·g⁻¹), with the highest found in Zhaoyang (S5). Most accessions exhibited high chemical similarity (>0.9), except for Yiliang (S12), which displayed a distinct profile. The partial correlation between SSR-based classifications and geographic origin, together with the inconsistency between phenotypic and chemical groupings, indicates that morphological variation is shaped by both environmental factors and complex genetic regulatory mechanisms. These findings provide a scientific basis for germplasm conservation, selective breeding, and the sustainable utilization of C. asiatica.