Weibing Zhuang

Drought stress is a major limiting factor during the process of plant growth and development, especially in arid and semi-arid regions. MYB transcription factors play vital roles in the regulation of many developmental processes under various stresses. The aim of this study was to determine whether PtrMYB119 enhanced dehydration tolerance in Nicotiana tabacum. PtrMYB119, with a weak transactivation activity, was distributed throughout the cell with no apparent specificity. The transgenic tobacco overexpressing PtrMYB119 might regulate dehydration tolerance through increased ABA content and antioxidant enzyme activities, decreased MDA levels, and up-regulation of antioxidant genes, polyamine biosynthesis genes, and drought-responsive genes. Overall, our results could contribute to the elucidation of drought tolerance underlying PtrMYB119 action in tobacco and indicated that PtrMYB119 could be exploited for engineering drought-enduring plants in the future.

Background: The floral color variegation of cultivar ‘Sahong Tao’ is distinctive and possesses significant ornamental value. Currently, there are no relevant reports on how MYB transcription factors (TFs) interact with LDOX promoter to regulate the flower color variegation in peach. Methods: In this study, we screened for proteins that interact with the LDOX promoter using yeast one-hybrid (Y1H) and next-generation sequencing (NGS). The NGS data were aligned with the Arabidopsis database (TAIR10) utilizing Python 3.10.4. PlantTFDB was employed to identify TFs, while PlantRegMap was used to predict TFs that interact with the LDOX promoter. The Y1H assay verified MYB1R1 interaction with LDOX promoter, and Y1H-AOS predicted their binding sites. The physicochemical properties, structure and interacting proteins of MYB1R1 were analyzed using bioinformatics methods. Sequence alignment and phylogenetic tree analyses of MYB1R1 were performed. Finally, the tissue expression specificity of MYB1R1 and LDOX in ‘Sahong Tao’ was examined using qRT-PCR. Results: The Y1H and NGS results indicate that 1,190 proteins interact with the LDOX promoter. Among these, 20 TFs were identified, including ERF, MYB, NF-YB, SBP, S1Fa-like, TCP, bHLH, LBD, ZF-HD, C3H, DBB, MYB-related, and HD-ZIP. Of the 1,190 proteins, 1,146 exhibit high similarity to homologs in Arabidopsis, with 332 classified as RNA binding proteins and 124 as DNA binding proteins. A comparison with the NGS results identified seven TFs that align with predictions from PlantRegMap. Based on these findings, we selected MYB44 (PRUPE_6G229000, PRUPE_1G430000) and MYB1R1 (PRUPE_5G182000) as candidate members. Y1H assays demonstrated that MYB1R1 interacts with the LDOX promoter. Y1H-AOS was used to confirm 24 interaction binding sites. MYB1R1 consists of an 897 bp full-length CDS, encoding 298 amino acids, with a predicted molecular weight of 32.49 kDa and a theoretical isoelectric point of 7.20. MYB1R1 features a typical SANT-MYB domain, and its secondary structure is predominantly composed of irregular coils. Phylogenetic analysis indicates a close evolutionary relationship between MYB1R1 from ‘Sahong Tao’ and both Prunus avium and Prunus speciosa. Promoter prediction analysis for MYB1R1 reveals multiple hormone- and stress-related cis-acting elements. MYB1R1 may interact with bHLH and other proteins to perform its functions. In variegated petals, MYB1R1 expression is higher and LDOX expression is lower compared to red petals, suggesting that MYB1R1 negatively regulates anthocyanin synthesis by interacting with LDOX. This study contributes to elucidating the function of MYB1R1 and the regulatory mechanism of MYB- LDOX in the flower color of ‘Sahong Tao’.

BHLH transcription factors, widely exist in various plants, and are vital for the growth and development of these plants. Among them, many have been implicated in anthocyanin biosynthesis across various plants. In the present... | Find, read and cite all the research you need on Tech Science Press

Environmental stresses, including abiotic and biotic stresses, have complex and diverse effects on the growth and development of woody plants, which have become a matter of contention due to concerns about the outcomes of climate change on plant resources, genetic diversity, and world food safety. Plant basic helix–loop–helix (bHLH) transcription factors (TFs) are involved in a variety of physiological processes and play an important role in biotic and abiotic stress responses of woody plants. In recent years, an increasing body of studies have been conducted on the bHLH TFs in woody plants, and the roles of bHLH TFs in response to various stresses are increasingly clear and precise. Therefore, it is necessary to conduct a systematic and comprehensive review of the progress of the research of woody plants. In this review, the structural characteristics, research history and roles in the plant growth process of bHLH TFs are summarized, the gene families of bHLH TFs in woody plants are summarized, and the roles of bHLH TFs in biotic and abiotic stresses in woody plants are highlighted. Numerous studies mentioned in this review have shown that bHLH transcription factors play a crucial role in the response of woody plants to biotic and abiotic stresses. This review serves as a reference for further studies about enhancing the stress resistance and breeding of woody plants. Also, the future possible research directions of bHLH TFs in response to various stresses in woody plants will be discussed.

The color of the leaves is one of the most important factors for horticultural crops that are considered by breeders, and is also attracting more and more attention from economists and academics. 'Quanhong poplar' (QHP), a rare, bright reddish-purple color-leaf cultivar that has been widely cultivated in China as a landscape tree, is a very precious color-leaf cultivar. In the present study, a reference-based assembly was performed using whole-genome sequencing data to characterize the chloroplast genome of 'QHP'. The total chloroplast genome size of 'QHP' is 156,950 bp, which is divided into two inverted repeat structures of 27,649 bp each, a small single-copy region of 16,563 bp, and a large single-copy region (LSC) of 85,089 bp. From the chloroplast genome, 130 genes have been predicted, including 85 protein-coding genes, 37 tRNA genes, and eight rRNA genes. A chloroplast genome containing 36.68% GC content was detected in 'QHP'. Three SNP sites have been developed between 'QHP' and Populus deltoides Zhonglin 2025. Based on the phylogenetic analysis of chloroplast genomes reported for Populus, the chloroplast of 'QHP' is closest to several strains of Populus deltoides.

Cadmium (Cd) pollution has attracted global attention because it not only jeopardizes soil microbial ecology and crop production, but also threatens human health. As of now, microbe-assisted phytoremediation has proven to be a promising approach for the revegetation of Cd-contaminated soil. Therefore, it is important to find such tolerant microorganisms. In the present study, we inoculated a bacteria strain tolerant to Cd, Cdb8-1, to Cd-contaminated soils and then explored the effects of Cdb8-1 inoculation on the performance of the Chinese milk vetch. The results showed plant height, root length, and fresh and dry weight of Chinese milk vetch grown in Cdb8-1-inoculated soils increased compared to the non-inoculated control group. The inoculation of Cd-contaminated soils with Cdb8-1 also enhanced their antioxidant defense system and decreased the H₂O₂ and malondialdehyde (MDA) contents, which alleviated the phytotoxicity of Cd. The inoculation of Cdb8-1 in Cd-contaminated soils attenuated the contents of total and available Cd in the soil and augmented the BCF and TF of Chinese milk vetch, indicating that the combined application of Cd-tolerant bacteria Cdb8-1 and Chinese milk vetch is a potential solution to Cd-contaminated soils.

With the climate constantly changing, plants suffer more frequently from various abiotic and biotic stresses. However, they have evolved biosynthetic machinery to survive in stressful environmental conditions. Flavonoids are involved in a variety of biological activities in plants, which can protect plants from different biotic (plant-parasitic nematodes, fungi and bacteria) and abiotic stresses (salt stress, drought stress, UV, higher and lower temperatures). Flavonoids contain several subgroups, including anthocyanidins, flavonols, flavones, flavanols, flavanones, chalcones, dihydrochalcones and dihydroflavonols, which are widely distributed in various plants. As the pathway of flavonoid biosynthesis has been well studied, many researchers have applied transgenic technologies in order to explore the molecular mechanism of genes associated with flavonoid biosynthesis; as such, many transgenic plants have shown a higher stress tolerance through the regulation of flavonoid content. In the present review, the classification, molecular structure and biological biosynthesis of flavonoids were summarized, and the roles of flavonoids under various forms of biotic and abiotic stress in plants were also included. In addition, the effect of applying genes associated with flavonoid biosynthesis on the enhancement of plant tolerance under various biotic and abiotic stresses was also discussed.

Tea (Camellia sinensis) is the second most consumed drink in the world. Rapid industrialization has caused various impacts on nature and increased pollution by heavy metals. However, the molecular mechanisms of cadmium (Cd) and arsenic (As) tolerance and accumulation in tea plants are poorly understood. The present study focused on the effects of heavy metals Cd and As on tea plants. Transcriptomic regulation of tea roots after Cd and As exposure was analyzed to explore the candidate genes involved in Cd and As tolerance and accumulation. In total, 2087, 1029, 1707, and 366 differentially expressed genes (DEGs) were obtained in Cd1 (with Cd treatment for 10 days) vs. CK (without Cd treatment), Cd2 (with Cd treatment for 15 days) vs. CK, As1 (with As treatment for 10 days) vs. CK (without Cd treatment), and As2 (with As treatment for 15 days) vs. CK, respectively. Analysis of DEGs showed that a total of 45 DEGs with the same expression patterns were identified in four pairwise comparison groups. One ERF transcription factor (CSS0000647) and six structural genes (CSS0033791, CSS0050491, CSS0001107, CSS0019367, CSS0006162, and CSS0035212) were only increased at 15 d of Cd and As treatments. Using weighted gene co-expression network analysis (WGCNA) revealed that the transcription factor (CSS0000647) was positively correlated with five structural genes (CSS0001107, CSS0019367, CSS0006162, CSS0033791, and CSS0035212). Moreover, one gene (CSS0004428) was significantly upregulated in both Cd and As treatments, suggesting that these genes might play important roles in enhancing the tolerance to Cd and As stresses. These results provide candidate genes to enhance multi-metal tolerance through the genetic engineering technology.

Chayote (Sechium edulel) fruits are rich in flavonoids, folate, and low-calorie food. However, studies about the flavonoids and the corresponding regulatory mechanism of flavonoid synthesis in chayote fruits was still unclear. In present study, an integrated transcriptome and metabolite analysis of chayote fruits at three different storage stages were conducted to explore the flavonoid compositions and gene expression associated with flavonoid synthesis. Through the UPLC-MS/MS analysis, a total of 57 flavonoid compounds were detected. Of these, 42 flavonoid glycosides were significantly differential accumulation in chayote fruits at three different storage stages. Many genes associated with flavonoid synthesis were differentially expressed in chayote fruits at three different storage stages through RNA-seq analysis, including structural genes and some TFs. There was a high correlation between RNA-seq analysis and metabolite profiling, and the expression level of candidate genes in the flavonoid synthesis pathway were consistent with the dynamic changes of flavonoids. In addition, one R2R3-MYB transcription factor, FSG0057100, was defined as the critical regulatory gene of flavonoid synthesis. Furthermore, exogenous application of phenylalanine increased the total content of flavonoids and promoted some flavonoid biosynthesis-related gene expression in chayote fruits. The above results not only make us better understand the molecular mechanism of flavonoid synthesis in chayote fruits, but also contribute to the promotion and application of chayote products.

Introduction: Colored-leaf plants are increasingly popular for their aesthetic, ecological, and social value, which are important materials for research on the regulation of plant pigments. However, anthocyanin components and the molecular mechanisms of anthocyanin biosynthesis in colored-leaf poplar remain unclear. Consequently, an integrative analysis of transcriptome and metabolome is performed to identify the key metabolic pathways and key genes, which could contribute to the molecular mechanism of anthocyanin biosynthesis in the colored-leaf cultivars poplar.Methods: In this study, integrated metabolite and transcriptome analysis was performed to explore the anthocyanin composition and the specific regulatory network of anthocyanin biosynthesis in the purple leaves of the cultivars ‘Quanhong’ (QHP) and ‘Zhongshanyuan’ (ZSY). Correlation analysis between RNA-seq data and metabolite profiles were also performed to explore the candidate genes associated with anthocyanin biosynthesis. R2R3-MYB and bHLH TFs with differential expression levels were used to perform a correlation analysis with differentially accumulated anthocyanins.Results and discussion: A total of 39 anthocyanin compounds were detected by LC-MS/MS analysis. Twelve cyanidins, seven pelargonidins, five delphinidins, and five procyanidins were identified as the major anthocyanin compounds, which were differentially accumulated in purple leaves of QHP and ZSY. The major genes associated with anthocyanin biosynthesis, including structural genes and transcription factors, were differentially expressed in purple leaves of QHP and ZSY through RNA-sequencing (RNA-seq) data analysis, which was consistent with quantitative real-time PCR analysis results. Correlation analysis between RNA-seq data and metabolite profiles showed that the expression patterns of certain differentially expressed genes in the anthocyanin biosynthesis pathway were strongly correlated with the differential accumulation of anthocyanins. One R2R3-MYB subfamily member in the SG5 subgroup, Podel.04G021100, showed a similar expression pattern to some structural genes. This gene was strongly correlated with 16 anthocyanin compounds, indicating that Podel.04G021100 might be involved in the regulation of anthocyanin biosynthesis. These results contribute to a systematic and comprehensive understanding of anthocyanin accumulation and to the molecular mechanisms of anthocyanin biosynthesis in QHP and ZSY.