Environmental stress is one of the major restrictions on plant development and foodstuff production. The adaptive response in plants largely occurs through an intricate signaling system, which is crucial for regulating the stress-responsive genes. Myelocytomatosis (MYC) transcription factors are the fundamental regulators of the jasmonate (JA) signaling branch that participates in plant development and multiple stresses. By binding to the cis-acting elements of a large number of stress-responsive genes, JA-responsive transcription factors activate the stress-resistant defense genes. The mechanism of stress responses concerns myriad regulatory processes at the physiological and molecular levels. Discovering stress-related regulatory factors is of great value in disclosing the response mechanisms of plants to biotic or abiotic stress, which could guide the genetic improvement of plant resistance. This review summarizes recent researches in various aspects of MYC2-mediated JA signaling and emphasizes MYC2 involvement in plant growth and stress response.

Dendrobium huoshanense is used to treat various diseases in traditional Chinese medicine. Recent studies have identified active components. However, the lack of genomic data limits research on the biosynthesis and application of these therapeutic ingredients. To address this issue, we generated the first chromosome-level genome assembly and annotation of D. huoshanense. We integrated PacBio sequencing data, Illumina paired-end sequencing data, and Hi-C sequencing data to assemble a 1.285 Gb genome, with contig and scaffold N50 lengths of 598 kb and 71.79Mb, respectively. We annotated 21,070 protein-coding genes and 0.96 Gb transposable elements, constituting 74.92% of the whole assembly. In addition, we identified 252 genes responsible for polysaccharide biosynthesis by Kyoto Encyclopedia of Genes and Genomes (KEGG) functional annotation. Our data provide a basis for further functional studies, particularly those focused on genes related to glycan biosynthesis and metabolism, and have implications for both conservation and medicine.

RNA can be modified by over 170 types of distinct chemical modifications, and the most abundant internal modification of mRNA in eukaryotes is N6-methyladenosine (m 6 A). The m 6 A modification accelerates mRNA process, including mRNA splicing, translation, transcript stability, export and decay. m 6 A RNA modification is installed by methyltransferase-like proteins (writers), and potentially removed by demethylases (erasers), and this process is recognized by m 6 A-binding proteins (readers). Notably, alterations of m 6 A-modified proteins (writers, erasers and readers) are involved in the tumorigenesis, progression and metastasis. Importantly, the fate of m 6 A-methylated mRNA is mediated mostly through m 6 A readers, and among these readers, insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) are unique RNA-binding proteins (RBPs) that stabilize their targets mRNA via m 6 A modification. In this review, we update the writers, erasers and readers, and their cross-talks in m 6 A modification, and briefly discuss the oncogenic role of IGF2BPs in cancer. Most importantly, we mainly review the up-to-date knowledges of IGF2BPs (IGF2BP1/2/3) as m 6 A readers in an m 6 A-modified manner in cancer progression.

The endophytic microbiome in medicinal plants is rich and diverse, but few studies have followed the endophytic microbiome of medicinal plants in different tissues with their growth. In this study, we examined the endophytic bacterial and fungal community structures associated with both the stem and root compartments of Dendrobium huoshanense at different growth years via high-throughput sequencing of 16S rRNA genes and nrDNA fragments of internal transcribed spacer regions. Results indicated that more diverse prokaryotic and fungal operational taxonomic units were detected in roots than in stems, and the alpha diversity of endophytic prokaryotic significantly differed among the 1-, 2-, and 3-year-old roots. The dominant bacterial phyla Proteobacteria Firmicutes, Actinobacteria, Bacteroidetes, and Acidobacteria, and fungal phyla Ascomycota, Basidiomycota, and Ascomycota were detected in the stems and roots with 3 growth years. Moreover, linear discriminant effect size analysis revealed 138 differentially abundant taxonomic clades in the bacterial level, and 197 in the fungal level in six groups. Our results provide evidence for endophytic microbiota communities depending on the tissues and growth years of D. huoshanense. The results from this study should be useful to better understand medicinal plant-microbe interactions.

Nitrogen-containing compounds especially alkaloids are important medicinal ingredients in caulis dendrobii plants. Using solid-phase extraction coupled with liquid chromatography tandem mass spectrometry and multivariate data analysis methods, metabolic profiling of the nitrogen-containing compounds was established to distinguish Dendrobium huoshanense and Dendrobium officinale. Hundreds of nitrogen-containing compounds from the two caulis dendrobii were purified by the MCX cartridges. Some compounds were identified by high-resolution tandem mass spectrometry technology. Together with multivariate data analysis methods, comparative analysis of the metabolic profiling from two caulis dendrobii was conducted. A total of 133 nitrogen-containing compounds were identified, including amino acids, pyrrolidines, tropanes, pyrimidines, purines, indoles, piperidines, guanidines, quinolines, isoquinolines and terpenoids. Metabolic profiling analysis showed that the composition and contents of these chemical components were significantly different between D. huoshanense and D. officinale.Moreover, some components were species-specific, distributed in the two caulis dendrobii, such as pilosine, ternatusine, etc. Because alkaloids are mainly derived from amino acids via multistep biochemical reactions, the correlation analysis suggested that amino acids were partially associated with several types of components and significantly correlated with certain alkaloids. Arginine was extremely correlated with guanidines. Pyrimidines, purines and niacin-nicotinamide metabolic intermediates were associated with three independent networks. The results further enriched the chemical components currently identified from caulis dendrobii and provided a technical reference for detecting nitrogen-containing compounds in other medicinal plants.