Project description:Plethodontid salamanders are the largest family of salamanders and are classic models for studying the effect of rapidly evolving courtship pheromones on mating behavior and reproductive success. Despite interests in plethodontid reproduction, very little is known about the molecular composition of salamander gametes, as the extraordinary sizes of their genomes have impaired the development of various omic-scale resources. To identify what proteins may be expressed in salamander sperm, we performed DIA-MS on sperm samples from two plethodontid species, Plethodon shermani and Desmognathus ocoee. As the first detailed study of salamander sperm, this study partially fills in a critical taxonomic gap in the study of fertilization proteins in vertebrates.
2022-04-18 | PXD030143 | Pride
Project description:Lung loss in plethodontid salamanders
Project description:Tissue regeneration is widely distributed across the tree of life. Among vertebrates, salamanders possess an exceptional ability to regenerate amputated limbs and other complex structures. Thus far, molecular insights about limb regeneration have come from a relatively limited number of species from two closely related salamander families. To gain broader perspective on the molecular basis of limb regeneration and enhance the molecular toolkit of an emerging plethodontid salamander (Bolitoglossa ramosi), we used RNA-seq to generate transcript sequence data and identify 602 genes that are differentially expressed during limb regeneration. This list was further processed to identify a core set of genes that exhibit conserved expression changes between B. ramosi and the Mexican axolotl (Ambystoma mexicanum), and presumably their common ancestor approximately 180 million years ago. Our study highlights the importance of developing comparative gene expression data for studies of limb regeneration among salamanders. All animals used in this work were collected under the Contract on Genetic Access for scientific research for non commercial profit (Contrato de acceso a recursos genéticos para la investigación científica sin interés commercial) to Resources number 118–2015.
2018-09-26 | GSE105232 | GEO
Project description:Testis and ovary transcriptome sequencing of plethodontid salamanders
Project description:<p>Psoriasis, a highly prevalent disease of humans of unknown cause, is a chronic inflammatory disorder primarily involving skin, with distinctive clinical characteristics. With the newly developed tools that facilitate microbiome research, it now is possible to assess whether the cutaneous microbiome plays a role in the pathogenesis of this disorder. Preliminary data from our studies suggest that the cutaneous microbiome in psoriasis is complex and possibly different from normal. To deal with this complexity, we propose to examine the cutaneous microbiome in relation to psoriasis with explorations at several taxonomic and informatic levels. Our overall objective is to examine how changes in the normal cutaneous microbiome contribute to the pathogenesis of psoriasis. Since causality is complex and often difficult to prove, and beyond the scope of this RFP, our overall hypothesis is that there are alterations in the cutaneous microbiome in areas of skin affected by psoriasis in comparison with the range observed in clinically unaffected areas, or in healthy persons. We also hypothesize that the characteristics of the microbiome may affect clinical responses to the immunomodulatory agents used to treat psoriasis. An alternative hypothesis is that effective treatment of psoriasis with systemic immunomodulatory agents will not substantially affect the disordered microbial ecosystem. Such observations would provide evidence for the roles of the microbiota in this disorder. Since an important consideration in microbiome research is the optimal level (e.g. phylum, genus, species, strain, gene) at which to examine a scientific question, and we are not yet certain what are the optimal levels for psoriasis, this also will be examined. Our studies of psoriasis should allow development of both approaches and tools that will have general utility for Microbiome research. To test our hypothesis, we propose the following specific aims: 1) To understand the cutaneous microbiome species composition overlaying psoriatic lesions; 2)To investigate differences in metagenome content for psoriatic lesions compared to normal skin; 3) To identify differences in the transcriptional profiles of the microbiome and the host between normal skin and psoriatic lesions using high-throughput sequencing; and 4) To estimate the effects of systemic immunomodulatory therapy for psoriasis on microbiome composition. In total, these studies should help us understand the role of the microbiome in psoriasis pathogenesis.</p> <p>We sought to characterize and compare the cutaneous microbiota of psoriatic lesions (lesion), unaffected contralateral skin from psoriatic patients (normal), and similar skin loci in matched healthy controls (control) in order to discern patterns that govern skin colonization and their relationship to clinical diagnosis. Using high-throughput 16S rRNA sequencing, we assayed the cutaneous bacterial communities of 51 matched triplets and characterized these samples using community data analysis techniques.</p>
Project description:Squalene makes up 12 % of human skin surface lipids, however little is known about its affects on the host skin microbiome. Here we tested the effect of squalene on genetic regulation of staphylococci, showing that it profoundly affects expression virulence or colonisation determinants, and of iron uptake systems.
Project description:Abstract: Natural communities of microbes inhabiting amphibian skin, the skin microbiome, are critical to supporting amphibian health and disease resistance. To enable the pro-active health assessment and management of amphibians on Army installations and beyond, we investigated the effects of acute (96h) munitions exposures to Rana pipiens (leopard frog) tadpoles and the associated skin microbiome, integrated with RNAseq-based transcriptomic responses in the tadpole host. Tadpoles were exposed to the legacy munition 2,4,6-trinitrotoluene (TNT), the new insensitive munition (IM) formulation, IMX-101, and the IM constituents nitroguinidine (NQ) and 1-methyl-3-nitroguanidine (MeNQ). The 96h LC50 values and 95% confidence intervals were 2.6 (2.4, 2.8) for ΣTNT and 68.2 (62.9, 73.9) for IMX-101, respectively. The NQ and MeNQ exposures caused no significant impacts on survival in 96h exposures even at maximum exposure levels of 3,560 and 5,285 mg/L, respectively. However, NQ and MeNQ, as well as TNT and IMX-101 exposures, all elicited changes in the tadpole skin microbiome profile, as evidenced by significantly increased relative proportions of the Proteobacteria with increasing exposure concentrations, and significantly decreased alpha-diversity in the NQ exposure. The potential for direct and indirect effects of munitions exposures on the skin microbiome were observed. A direct effect of munitions on microbial flora included the observation of increased relative abundance of the munitions-tolerant, Aeromonadaceae and Pseudomonadaceae, in the NQ exposure. Potential indirect effects on the tadpole skin microbiome resulting from tadpole-host responses to munitions included transcriptional responses indicative of potential changes in skin mucus-layer properties as well as altered production of antimicrobial peptides and innate immune factors. Additional insights into the tadpole host’s transcriptional response to munitions exposures indicated that TNT and IMX-101 exposures each elicited significant enrichment of pathways involved in type-I and type-II xenobiotic metabolism mechanisms where dose-responsive increases in expression were observed. Significant enrichment and increased transcriptional expression of heme and iron binding functions in the TNT exposures was likely connected with known mechanisms of TNT toxicity including hemolytic anemia and methemoglobinemia. The significant enrichment and dose-responsive decrease in transcriptional expression of cell cycle pathways in the IMX-101 exposures was consistent with previous observations in fish, while significant enrichment of immune-related function in response to NQ exposure indicated potential immune suppression at the highest NQ exposure concentration. Finally, the MeNQ exposures elicited significantly decreased transcriptional expression of keratin 16, type I, a gene likely involved in keratinization processes in amphibian skin. Overall, munitions showed the potential to alter tadpole skin microbiome composition and affect transcriptional profiles in the amphibian host, some indicative of potentially impacted host health and immune status, each of which suggest potential implications for munitions exposure on disease susceptibility.
Project description:On going efforts are directed at understanding the mutualism between the gut microbiota and the host in breast-fed versus formula-fed infants. Due to the lack of tissue biopsies, no investigators have performed a global transcriptional (gene expression) analysis of the developing human intestine in healthy infants. As a result, the crosstalk between the microbiome and the host transcriptome in the developing mucosal-commensal environment has not been determined. In this study, we examined the host intestinal mRNA gene expression and microbial DNA profiles in full term 3 month-old infants exclusively formula fed (FF) (n=6) or breast fed (BF) (n=6) from birth to 3 months. Host mRNA microarray measurements were performed using isolated intact sloughed epithelial cells in stool samples collected at 3 months. Microbial composition from the same stool samples was assessed by metagenomic pyrosequencing. Both the host mRNA expression and bacterial microbiome phylogenetic profiles provided strong feature sets that clearly classified the two groups of babies (FF and BF). To determine the relationship between host epithelial cell gene expression and the bacterial colony profiles, the host transcriptome and functionally profiled microbiome data were analyzed in a multivariate manner. From a functional perspective, analysis of the gut microbiota's metagenome revealed that characteristics associated with virulence differed between the FF and BF babies. Using canonical correlation analysis, evidence of multivariate structure relating eleven host immunity / mucosal defense-related genes and microbiome virulence characteristics was observed. These results, for the first time, provide insight into the integrated responses of the host and microbiome to dietary substrates in the early neonatal period. Our data suggest that systems biology and computational modeling approaches that integrate “-omic” information from the host and the microbiome can identify important mechanistic pathways of intestinal development affecting the gut microbiome in the first few months of life. KEYWORDS: infant, breast-feeding, infant formula, exfoliated cells, transcriptome, metagenome, multivariate analysis, canonical correlation analysis 12 samples, 2 groups
Project description:The gut microbiome shapes local and systemic immunity. The liver is presumed to be a protected sterile site. As such, a hepatic microbiome has not been examined. Here, we show that the liver hosts a robust microbiome in mice and humans that is distinct from the gut and is enriched in Proteobacteria. It undergoes dynamic alterations with age and is influenced by the environment and host physiology. Fecal microbial transfer experiments revealed that the liver microbiome is populated from the gut in a highly selective manner. Hepatic immunity is dependent on the microbiome, specifically Bacteroidetes species. Targeting Bacteroidetes with oral antibiotics reduced the hepatic immune cell infiltrate by ~90%, prevented APC maturation, and mitigated adaptive immunity. Mechanistically, presentation of Bacteroidetes-derived glycosphingolipids to NKT cells promotes CCL5 signaling, which drives hepatic leukocyte expansion and maturation. Collectively, we reveal a microbial – glycosphingolipid – NKT – CCL5 axis that underlies hepatic immunity.