Project description:Herein, we evaluated the changes in biological functions in soils across global biomes through the identification and quantification of proteins. This knowledge is essential to provide one stepforward in soil microbial ecology in order to decipher the cellular and molecular mechanisms employed by soil microbial communities to adapt to their environment and to explain the potential responses of microbial communities, and their microbially-driven ecosystem services, to global change and land use. Our study aims to provide the most comprehensive assessment on the structure and function of the topsoil metaproteome across global biomes, and hence provide direct identification of the most domimant protein-encoded functions in terrestrial ecosystems.
Project description:The prognostic factors of skull base chordoma associated with outcomes of patients after surgical resection remain poorly defined. This project aimed to identify a novel prognostic factor for patients with skull base chordoma. Using a proteomics approach, we screened tumor biomarkersthat upregulated in the rapid-recurrence group of chordoma, narrowed down by bioinformatics analysis, and finally potential biomarker was chosen for validation by immunohistochemistry using tissue microarray.
Project description:The study of 5-hydroxylmethylcytosines (5hmC), the sixth base of the mammalian genome, as an epigenetic mark has been hampered by a lack of method to map it at single-base resolution. Previous affinity purification-based methods could not precisely locate 5hmC nor accurately determine its relative abundance at each modified site. We here present a genome-wide approach for mapping 5hmC at base resolution. Application of this new method to the embryonic stem cells not only confirms widespread distribution of 5hmC in mammalian genome, but also reveals a strong sequence bias and strand asymmetry at sites of 5hmC. Additionally, the relative abundance of 5hmC varies significantly depending on the types of functional sequences, suggesting different mechanisms for 5hmC deposition and maintenance. Furthermore, we observe high levels of 5hmC and reciprocally low levels of 5mC at transcription factor binding sites, revealing a dynamic DNA methylation process at cis-regulatory elements. Base resolution sequencing of 5 hydroxymethylcytosine in human and mouse embryonic stem cells
Project description:We have combined standard micrococcal (MNase) digestion of nuclei with a modified protocol for construction paired-end DNA sequencing libraries to map both nucleosomes and subnucleosome-sized particles at single base-pair resolution throughout the budding yeast genome. We found that partially unwrapped nucleosomes and subnucleosome-sized particles can occupy the same position within a cell population, suggesting dynamic behavior. By varying the time of MNase digestion, we have been able to observe changes that reflect differential sensitivity of particles, including eviction of nucleosomes. Our protocol and mapping method provide a general strategy for characterizing full epigenomes. We used micrococcal nuclease mapping, chromatin immunoprecipitation and paired-end sequencing to determine the structure of yeast centromeres at single base-pair resolution.
Project description:Cytosine base modifications 5-methylcytosine (5mC), 5-hydroxymethylcytosine (5hmC) and 5-formylcytosine (5fC) are present in mammalian DNA. Here, reduced bisulfite sequencing is developed for quantitatively sequencing 5fC at single-base resolution. This method is then applied with oxidative bisulfite sequencing to gain a map of 5mC, 5hmC and 5fC in mouse embryonic stem cells. 12 samples, reduced representation bisulphite treatment: 4 replicates each for bisulphite (BS), oxidative BS (oxBS) and reduced BS (redBS) for the detection of 5mC, 5hmC and 5fC. Mouse (strain B6C) embryonic stem cells.
Project description:We report transcriptome wide edits comparison between split-engineered base editors and intact base editors. Our results show that, split-engineered base editors show backgound levels of unique C>U edits when compared to intact base editors.
Project description:The immunodeficiency, centromere instability and facial anomalies (ICF) syndrome is associated with mutation of the DNA methyl-transferase DNMT3B, resulting in a reduction of enzyme activity. Aberrant expression of immune system genes and hypomethylation of pericentromeric regions accompanied by chromosomal instability were determined as alterations driving the disease phenotype. However, so far only technologies capable of analyzing single loci were applied to determine epigenetic alterations in ICF patients. In the current study, we performed whole-genome bisulphite sequencing to assess alteration in DNA methylation at base-pair resolution. Whole-genome bisulphite sequencing was performed to assess alteration in DNA methylation of one ICF patient and one healthy control sample at base-pair resolution.