Project description:miR-145 is downregulated in multiple cancers. The introduction of miR-145 could alleviate the tumor burden in the pancreatic cancer mouse model. However, how miR-145 mediates the tumor suppression is still an open question. In this study, we aimed to identify the targets of miR-145 using a SILAC approach.
Project description:Kombucha, a fermented tea generated from the co-culture of yeasts and bacteria, has gained worldwide popularity in recent years due to its potential benefits to human health. As a result, many studies have attempted to characterize both its biochemical properties and microbial composition. Here, we have applied a combination of whole metagenome sequencing (WMS) and amplicon (16S rRNA and Internal Transcribed Spacer 1 [ITS1]) sequencing to investigate the microbial communities of homemade Kombucha fermentations from day 3 to day 15. We identified the dominant bacterial genus as Komagataeibacter and dominant fungal genus as Zygosaccharomyces in all samples at all time points. Furthermore, we recovered three near complete Komagataeibacter genomes and one Zygosaccharomyces bailii genome and then predicted their functional properties. Also, we determined the broad taxonomic and functional profile of plasmids found within the Kombucha microbial communities. Overall, this study provides a detailed description of the taxonomic and functional systems of the Kombucha microbial community. Based on this, we conject that the functional complementarity enables metabolic cross talks between Komagataeibacter species and Z. bailii, which helps establish the sustained a relatively low diversity ecosystem in Kombucha.
Project description:Kombucha Tea (KT), a fermented tea with roots in traditional Chinese medicine, has surged in worldwide popularity due to its purported health benefits. KT contains a symbiotic culture of yeast and bacterial species, many of which are considered human probiotics. The molecular basis of the health benefits of KT has yet to be thoroughly explored in any animal model. We establishC. elegansas a model to query the molecular interactions between Kombucha-associated microbes (KTM) and the host. We find that worms have an established gut microbiome after consuming a KTM-exclusive diet that mirrors the microbial community found in the fermenting culture. Remarkably, animals consuming KTMs display strikingly reduced lipid levels, yet develop and reproduce similarly toE. coli-fed animals. Critically, consumption of a non-fermenting mix of KT microbial isolates (Kombucha microbe mix) resulted in elevated fat accumulation, suggesting that KTMs do not impair nutrient absorption. To identify the host metabolic pathways altered by KTMs, we performed mRNA-seq on KTM-fed animals, finding widespread changes in lipid metabolism genes. Specifically, we found that three lysosomal lipase genes are significantly upregulated in these animals. These lipases, LIPL-1-3, have been previously shown to promote lipophagy via catabolism of lipid droplets. Consistently, KTM-fed animals display reduced levels of triglycerides and smaller lipid droplet sizes. We propose that KTM-fed animals exhibit a fasting-like metabolic state, even in the presence of sufficient nutrient availability, possibly through induction of lipophagy. Elucidating the host metabolic response to KT consumption will provide unprecedented insight into how this popular fermented beverage may impact human health and inform its use in complementary healthcare plans.
Project description:Kombucha fermentation is initiated by transferring a solid-phase cellulosic pellicle into sweetened tea and allowing the microbes that it contains to initiate the fermentation. This pellicle, commonly referred to as a symbiotic culture of bacteria and yeast (SCOBY), floats to the surface of the fermenting tea and represents an interphase environment, where embedded microbes gain access to oxygen as well as nutrients in the tea. To date, various yeast and bacteria have been reported to exist within the SCOBY, with little consensus as to which species are essential and which are incidental to Kombucha production. In this study, we used high-throughput sequencing approaches to evaluate spatial homogeneity within a single commercial SCOBY and taxonomic diversity across a large number (n = 103) of SCOBY used by Kombucha brewers, predominantly in North America. Our results show that the most prevalent and abundant SCOBY taxa were the yeast genus Brettanomyces and the bacterial genus Komagataeibacter, through careful sampling of upper and lower SCOBY layers. This sampling procedure is critical to avoid over-representation of lactic acid bacteria. K-means clustering was used on metabarcoding data of all 103 SCOBY, delineating four SCOBY archetypes based upon differences in their microbial community structures. Fungal genera Zygosaccharomyces, Lachancea and Starmerella were identified as the major compensatory taxa for SCOBY with lower relative abundance of Brettanomyces. Interestingly, while Lactobacillacae was the major compensatory taxa where Komagataeibacter abundance was lower, phylogenic heat-tree analysis infers a possible antagonistic relationship between Starmerella and the acetic acid bacterium. Our results provide the basis for further investigation of how SCOBY archetype affects Kombucha fermentation, and fundamental studies of microbial community assembly in an interphase environment.
Project description:miR-145 is a tumor suppressor miRNA in various malignancies including pancreatic cancer. How miR-145 regulates expression of other miRNAs could provide a panoramic view of the development of pancreatic cancer. Therefore, in this project, we aimed to characterize how other miRNAs are affected by miR-145 in hope for understanding proteomic changes that are not explained by miR-145 alone.
Project description:miR-145 is a tumor suppressor miRNA in various malignancies including pancreatic cancer. Identification of miR-145 targets can lead to more understanding of the development of pancreatic cancer. Therefore, in this project, we aimed to characterize the changes of transcriptomes caused by miR-145 to identify more miR-145 target transcripts.