Project description:Boreal toads (Anaxyrus boreas boreas) of the Southern Rocky Mountain population are declining due to the introduction of the chytrid fungus Batrachochytrium dendrobatidis (Bd). Boreal toads in Colorado are generally susceptible to Bd infection, but some Bd-tolerant populations persist in parts of the Southern Rocky Mountain and broader Eastern boreal toad population. We conducted a Bd challenge with lab-reared sibling toads from Bd-susceptible Colorado and purportedly Bd-tolerant Utah populations and report on transcriptomic responses to Bd during late infection in skin and liver tissue. Fewer immune genes were expressed in response to Bd in Colorado toads, but with greater upregulation compared to Utah toads, indicating a dysregulated immune response. Signatures of Bd-tolerance in Utah toads included more moderate upregulation in immune gene expression and a significantly enriched suite of gene functions related to innate and adaptive immune responses. Our transcriptomic results support the notion that Utah toads are tolerant to Bd, rather than resistant, carrying Bd loads similar to Colorado yet having a unique transcriptomic profile and presenting minimal clinical signs of chytridiomycosis. We conclude that closely related populations have divergent transcriptomic responses to Bd with a dysregulated immune response in Bd-susceptible toads.
2023-10-04 | GSE244617 | GEO
Project description:Full-length Transcriptome Analysis Reveals Candidate Genes Involved in Terpenoid Biosynthesis in Artemisia argyi
| PRJNA722539 | ENA
Project description:Full-length Transcriptome Analysis Reveals Candidate Genes Involved in Terpenoid Biosynthesis in Artemisia argyi
Project description:Despite extensive research, there is still limited knowledge of the functional biology of most animal toxins, including their venom production and storage, as well as the morphological structures within sophisticated venom producing tissues that might underpin venom modulation. Here we applied non-targeted mass spectrometry imaging (MSI), in combination with standard proteomic and transcriptomic approaches, to enable discrete toxin mapping in high-resolution intensity maps across a snake venom gland sourced from the Egyptian cobra (Naja haje). Matrix-assisted laser desorption/ionization (MALDI) MSI toxin visualization on the elapid venom gland reveals surprising spatial heterogeneity of different toxin classes at the proteoform level, which may be the result of physiological constraints on venom production and/or storage, or reflect the potential for venom modulation under different stimuli.
Project description:Purpose: Corals are major sources of dimethylsulphoniopropionate (DMSP), a compound that plays a central role in the global sulphur cycle. While DMSP biosynthesis pathways have been investigated in plants and algae, the molecular basis for its production by corals is unknown. Given its potential role as an osmolyte, the effect of salinity stress on levels of DMSP was investigated in both adults and juveniles (lacking photosynthetic symbionts) of the coral Acropora millepora. This study used transcriptomic data to analyse the effects of salinity over the coral A. millepora and to identify coral genes likely to be involved in DMSP biosynthesis. Methods: Adults coral transcriptomic libraries were constructed from samples exposed during 1 and 24 hours of salinity treatment (25 PSU) and control (35 PSU) conditions (n=5 per condition). Juveniles coral transcriptomic libraries were constructed from samples exposed to 24 and 48 hours of salinity treatment (28 PSU) and control (35 PSU) conditions (n=6 per condition). All libraries were sequenced by 100 bp paired-end in a HiSeq 2000. Reads were mapped onto the Acropora millepora genome using TopHat2 to produce a count data gene expression matrix for subsequent gene expression analysis using DESeq2 package. Results: In adult coral samples, 5.5 - 10.2 million RNAseq reads were obtained for each treatment sampling time while 3.4 - 8.8 million reads were obtained for each juvenile coral sample. The count matrix of the 26,622 A. millepora gene predictions were generated using htseq-count workflow. BlastP analysis of the A. millepora gene predictions led to the identification of coral members of gene families implicated in DMSP biosynthesis in other organisms, while RNA-seq data was used to identify the differentially expressed ones in response to hyposaline stress and on this basis were considered to be candidates for roles in DMSP biosynthesis in corals. Conclusions: Hyposaline stress increased DMSP production in both adults and aposymbiotic juvenile corals, and transcriptomic analyses highlighted the potential involvement of specific candidate genes in the production of DMSP via an alga-like pathway. The biochemistry of DMSP production is not well established for any eukaryotic system and, as the first animals in which it has been demonstrated, this is particularly true in the case of corals. Our RNA-seq results enabled the identification of candidates for roles in DMSP biosynthesis in corals but, given its critical roles in diverse biological processes, a thorough investigation of the molecular mechanisms leading to its production by corals is required.
Project description:Toxins TcdA and TcdB are the main virulence factors of Clostridioides difficile, a leading cause of hospital-acquired diarrhea. We investigated the therapeutic potential of inhibiting the biosynthesis of TcdA and TcdB. Accordingly, screening of structurally diverse phytochemicals with medicinal properties identified 18b-glycyrrhetinic acid (enoxolone) as an inhibitor of TcdA and TcdB biosynthesis. Enoxolone also inhibited sporulation. In a CDI colitis model, enoxolone when combined with vancomycin protected mice from becoming moribund and the combination was more effective than vancomycin alone, a standard of care antibiotic for CDI. While enoxolone alone reduced the in vivo load of toxins, the monotherapy did not protect mice from CDI. Affinity based proteomics identified ATP synthase subunit alpha (AtpA) and adenine deaminase (Ade) as possible molecular targets for enoxolone. Silencing of mRNA for Ade and AtpA also reduced toxin biosynthesis, while molecular interaction analysis showed that enoxolone directly bound to Ade. Ade converts adenine to hypoxanthine as an early step in the purine salvage pathway. Metabolomics revealed enoxolone caused cells to accumulate adenosine and deplete hypoxanthine and ATP. Accordingly, supplementation with hypoxanthine partly restored toxin production. Enoxolone also impacted phosphate metabolism by reducing the amounts of cellular phosphate. Thus, supplementation with triethyl phosphate as a source of phosphate also partly restored toxin production. When hypoxanthine and triethyl phosphate were combined, toxin production was fully restored in the presence of enoxolone. Taken together, studies with enoxolone revealed metabolic pathways that affect C. difficile toxin production and could represent potential anti-virulence drug targets.
Project description:De novo transcriptome assembly and characterization of nine tissues of Lonicera japonica to identify potential candidate genes involved in chlorogenic acid, luteolosides, and secoiridoid biosynthesis pathways