Project description:<p>Rhododendron species have the potential to be rich in secondary metabolites with pharmaceutical or industrial value. However, there is a lack of in comprehensive metabolome studies at the genome level, particularly for unique and rare species like R. bailiense which exclusively grows in karst environments in Guizhou, southwest China. Recently, genome assembly data for this species was available. In this study, non-targeted metabolomics was employed to investigate the secondary metabolites profile of R. bailiense callus. The callus of R. bailiense was induced using 0.2 mg/L TDZ (Thidiazuron) + 0.1 mg/L IBA (3-Indole butyric acid). A comparison between light-treated calli and dark-cultured calli revealed differential accumulation of metabolites, particularly in flavonoids, terpenoids, coumarins and hydroxycinnamic acids, known for their beneficial effects such as antioxidant, anticancer and anti-inflammatory properties. Proanthocyanidins, with various health-promoting effects, were found to accumulate significantly in dark-cultured calli. Light conditions promoted diterpene and triterpene products, whereas darkness favored sesquiterpene products. Additionally, the study demonstrated the potential of utilizing Agrobacterium transformation technology on callus suspension cells to enhance secondary metabolite production. Comparison with the genome of R. molle revealed that the R. bailiense genome exhibited active 'glycosyltransferase activity', possessed a higher number of copies of monoterpene and sesquiterpene terpene synthases, and contained high copies of specific cytochrome P450 members (CYP71, CYP76, CYP79, CYP82, CYP736). This study offers valuable insights and potential strategies for the biosynthesis and production of Rhododendron secondary metabolites with pharmaceutical or industrial significance.</p>
Project description:Most of the human genome is thought to be non-functional, and includes large segments often referred to as “dark matter” DNA. The genome also encodes hundreds of putative and poorly characterized transcription factors (TFs). We determined genomic binding locations of 166 uncharacterized human TFs in living cells. Nearly half of them associated strongly with known regulatory regions such as promoters and enhancers, often at conserved motif matches and co-localizing with each other. Surprisingly, the other half often associated with genomic dark matter, at largely unique sites, via intrinsic sequence recognition. Dozens of these, which we term “Dark TFs” mainly bind within regions of closed chromatin. Dark TF binding sites are rarely under purifying selection, and are enriched for transposable elements. Many Dark TFs are KZNFs, which contain the repressive KRAB domain, but many are not, and may represent potential pioneer TFs: based on compiled literature information, the Dark TFs exert diverse functions ranging from early development to tumor suppression. Thus, a large fraction of previously uncharacterized human TFs may have unappreciated activities within the dark matter genome.
Project description:Most of the human genome is thought to be non-functional, and includes large segments often referred to as “dark matter” DNA. The genome also encodes hundreds of putative and poorly characterized transcription factors (TFs). We determined genomic binding locations of 166 uncharacterized human TFs in living cells. Nearly half of them associated strongly with known regulatory regions such as promoters and enhancers, often at conserved motif matches and co-localizing with each other. Surprisingly, the other half often associated with genomic dark matter, at largely unique sites, via intrinsic sequence recognition. Dozens of these, which we term “Dark TFs” mainly bind within regions of closed chromatin. Dark TF binding sites are rarely under purifying selection, and are enriched for transposable elements. Many Dark TFs are KZNFs, which contain the repressive KRAB domain, but many are not, and may represent potential pioneer TFs: based on compiled literature information, the Dark TFs exert diverse functions ranging from early development to tumor suppression. Thus, a large fraction of previously uncharacterized human TFs may have unappreciated activities within the dark matter genome.
Project description:Most of the human genome is thought to be non-functional, and includes large segments often referred to as “dark matter” DNA. The genome also encodes hundreds of putative and poorly characterized transcription factors (TFs). We determined genomic binding locations of 166 uncharacterized human TFs in living cells. Nearly half of them associated strongly with known regulatory regions such as promoters and enhancers, often at conserved motif matches and co-localizing with each other. Surprisingly, the other half often associated with genomic dark matter, at largely unique sites, via intrinsic sequence recognition. Dozens of these, which we term “Dark TFs” mainly bind within regions of closed chromatin. Dark TF binding sites are rarely under purifying selection, and are enriched for transposable elements. Many Dark TFs are KZNFs, which contain the repressive KRAB domain, but many are not, and may represent potential pioneer TFs: based on compiled literature information, the Dark TFs exert diverse functions ranging from early development to tumor suppression. Thus, a large fraction of previously uncharacterized human TFs may have unappreciated activities within the dark matter genome.