Botrytis cinerea is considered the second most important fungal plant pathogen, and can cause serious disease, especially on tomato. The TPK1b gene encodes a receptor-like kinase that can positively regulate plant resistance to B. cinerea. Here, we identified a tomato WRKY transcription factor SlWRKY3 that binds to the W-box on the TPK1b promoter. It can negatively regulate TPK1b transcription, then regulate downstream signaling pathways, and ultimately negatively regulate tomato resistance to B. cinerea. SlWRKY3 interference can enhance resistance to B. cinerea, and SlWRKY3 overexpression leads to susceptibility to B. cinerea. Additionally, we found that B. cinerea can significantly, and rapidly, induce the upregulation of SlWRKY3 expression. In SlWRKY3 transgenic plants, the TPK1b expression level was negatively correlated with SlWRKY3 expression. Compared with the control, the expression of the SA pathway marker gene PR1 was downregulated in W3-OE plants and upregulated in W3-Ri plants when inoculated with B. cinerea for 48 h. Moreover, SlWRKY3 positively regulated ROS production. Overall, SlWRKY3 can inhibit TPK1b transcription in tomato, and negatively regulate resistance to B. cinerea by modulating the downstream SA and ROS pathways.

The rose (Rosa chinensis), with its rich color variations and elegant form, holds a significant position in the global floriculture industry, where the color of its petals and the content of anthocyanins are crucial for enhancing the plant’s ornamental value and market competitiveness. Nevertheless, the precise roles of the GST gene family in roses, especially regarding their participation in anthocyanin transport and the modulation of petal color, remain poorly elucidated. In the present investigation, we identified 83 rose glutathione S-transferase (GST) genes through whole-genome analysis. The identification and functional analysis of RcGSTF2 were conducted exclusively in the ‘Old Blush’ cultivar of Rosa chinensis. We employed bioinformatics, tissue expression analysis, subcellular localization, and transient expression validation to explore the function of the RcGSTF2 gene in anthocyanin transport and accumulation. We found that RcGSTF2 is closely related to anthocyanin-associated GSTs and demonstrated a conserved domain with high sequence similarity. Molecular docking analysis revealed potential binding modes between RcGSTF2 and cyanidin-3,5-diglucoside, suggesting a role in anthocyanin transport. Subcellular localization indicated that RcGSTF2 is associated with the cell membrane. Overexpression of RcGSTF2 in rose plants significantly increased anthocyanin accumulation, while silencing RcGSTF2 reduced anthocyanin content, highlighting its crucial role in regulating anthocyanin accumulation. This research investigates the functions of the GST gene family in roses, laying the groundwork for developing more colorful and resilient rose cultivars, with the functional analysis of RcGSTF2 being a key contribution to the floriculture industry’s genetic enhancement efforts.

Carrots accumulate numerous carotenoids in the root, resulting in different colors. Orange carrots are primarily high in α- and β-carotene, while yellow carrots are packed with lutein. This study was designed to explore the molecular mechanism underlying the yellow mutation involving lutein using a recently obtained yellow root mutant carrot (ym) via mutagenesis of an orange root wild type (wt). Microscopes were used to observe the variations in histological and cellular structures, and transcriptome and resequencing analyses were conducted for ym and wt. The root callus of ym contained fewer colored crystals and globular chromoplasts than those of wt. Based on ribonucleic acid sequencing (RNA-seq) data analysis, 19 photosynthesis-related differentially expressed genes (DEGs) were enriched. Among them, there were 6 photosynthesis-related genes experiencing nonsynonymous mutations, including PSAL, PSB27-1, psbB, and three homologs of LHCB1.3, and Lut 5, the mapped gene regulating lutein content in carrot root, also had nonsynonymous mutations in ym. These 7 genes were shown to be significantly differently expressed at one or more time points during the lutein accumulation process. It is predicted that the 6 photosynthesis-related genes and Lut 5 are candidate genes for lutein accumulation, which results in root color mutation. The candidate genes identified in this study can provide a new insight into the molecular mechanism of lutein modulation.

Gray mold caused by Botrytis cinerea poses a severe threat to tomato production. In this study, physiological, biochemical, transcriptomic, and proteomic analyses were integrated to characterize the dynamic responses of tomato ‘Ailsa Craig’ to B. cinerea infection. During B. cinerea infection, peroxidase (POD) activity showed a progressive increase, while catalase (CAT) activity was significantly upregulated at 24 hpi and remained stable through 48 hpi. Malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) contents showed a delayed response, increasing significantly only at 48 hpi, whereas SOD activity exhibited a biphasic pattern. Transcriptome and proteome profiling identified 5824 differentially expressed genes and 124 differentially expressed proteins. Functional enrichment analysis highlighted defense-related pathways, including plant–pathogen interaction, flavonoid biosynthesis, and inositol phosphate metabolism. Notably, the chlorophyll a/b-binding protein SlLhcb13 exhibited post-transcriptional upregulation despite transcriptional suppression. Functional validation demonstrated that overexpression of SlLhcb13 enhanced resistance, whereas silencing increased susceptibility. These findings identify SlLhcb13 as a positive regulator linking photosynthesis to immunity and provide new insights into the defense mechanisms of tomato.

Lycopene (carotenoid) is a natural pigment with strong antioxidant properties. The taproots of red carrots (Daucus carota L.) exhibit red coloration due to the presence of high levels of lycopene. However, the candidate genes responsible for regulating lycopene accumulation in red carrots have yet to be identified. In this study, the variations in carotenoid content were assessed at five different stages of taproot development. The results showed a rapid accumulation of lycopene in the taproots between 45 and 60 days after sowing, peaking at its highest level by 75 days. Weighted Gene Co-expression Network Analysis (WGCNA) was used to construct co-expression modules associated with lycopene accumulation. Notably, two of the identified modules (red and mediumpurple3) exhibited significant correlations with lycopene content. A total of 24 differentially expressed genes (DEGs) were enriched by both Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, and one carotenoid pathway gene was only enriched by KEGG analysis. Among these genes, five genes associated with photosynthesis (DCAR_016944 [DcCHL27], DCAR_021505 [DcFNR2], DCAR_000568 [DcPSB28], DCAR_030558 [DcBPG1], and DCAR_030562 [DcBPG1]) and one carotenoid pathway gene (DCAR_013459 [DcCRTISO-1]) were highly connected hub genes. These six genes were significantly up-regulated at 60 and 75 days after sowing, when the taproots accumulated high lycopene content, and were identified as candidate genes. These findings contribute valuable insights into the molecular mechanisms underlying the modulation of lycopene.