Project description:Investigation of the phylogenetic diversity of Acidobacteria taxa using PCR amplicons from positive control 16S rRNA templates and total genomic DNA extracted from soil and a soil clay fraction
Project description:A phylogenetic microarray targeting 66 families described in the human gut microbiota has been developped aud used to monitor the gut microbiota's structure and diversity. The microarray format provided by Agilent and used in this study is 8x15K. A study with a total of 4 chips was realized. Arrays 1 and 2: Hybridization with 100ng of labelled 16S rRNA gene amplicons from a mock community sample and 250ng of labelled 16S rRNA gene amplicons from 1 faecal sample. Each Agilent-030618 array probe (4441) was synthetized in three replicates. Arrays 3 and 4: Hybridization with 250ng of labelled 16S rRNA gene amplicons from 2 faecal samples. Each Agilent-40558 array probe (4441) was synthetized in three replicates.
Project description:Investigation of the phylogenetic diversity of Acidobacteria taxa using PCR amplicons from positive control 16S rRNA templates and total genomic DNA extracted from soil and a soil clay fraction A ten chip study using PCR amplicons from cloned 16S rRNA genes and from diverse soil 16S rRNAs, with PCR primers specific to the Division Acidobacteria. Each chip measures the signal from 42,194 probes (in triplicate) targeting Acidobacteria division, subdivision, and subclades as well as other bacterial phyla. All samples except one (GSM464591) include 2.5 M betaine in the hybridization buffer. Pair files lost due to a computer crash.
Project description:Single-cell genomics and single-cell transcriptomics have recently emerged as powerful tools to study the biology of single cells at a genome-wide scale. Here we describe a method that allows the integration of genomic DNA and mRNA sequencing from the same cell. We use this method to correlate DNA copy number variation to transcriptome variability among individual cells. First, hand-picked single cells are lysed and reverse transcribed using a poly-A primer including cell-specific barcodes, a 5' Illumina adapter and a T7 promoter overhang to convert mRNA to single stranded cDNA (ss cDNA). The gDNA and single stranded cDNA are then subjected to quasilinear whole genome amplification, as previously described, using an adapter with a defined 27 nucleotide sequence at the 5M-bM-^@M-^Y end followed by 8 random nucleotides. After 7 rounds of amplification, the gDNA and cDNA are copied to generate a variety of different short amplicon (0.5M-bM-^@M-^S2.5 kb) species, with a majority of amplicons containing adapter Ad-2 at both ends and a small fraction of cDNA derived amplicons containing Ad-2 at one end and Ad-1x at the other. Next, the sample is split into two tubes to further amplify gDNA and cDNA. The tube used to sequence gDNA is amplified using PCR. Following sonication, adapter Ad-2 removal, and cell-specific indexed Illumina library preparation, this half is used to sequence gDNA. The tube used to sequence cDNA is converted to double-stranded cDNA and amplified using in vitro transcription such that the amplified RNA (aRNA) is uniquely produced from cDNA but not gDNA. 3M-bM-^@M-^Y Illumina adapters are then ligated to the aRNA followed by reverse transcription and PCR, allowing quantification of mRNA.
Project description:Anthropogenic nutrient inputs alter soil biodiversity; however, it remains largely unknown whether changes in soil microeukaryotes (fungi and protists) are primarily driven by direct effects, such as modifications in soil properties, or by indirect effects, such as plant diversity loss. To disentangle these mechanisms, we investigated the long-term effects (11 years) of fertilization and manipulated plant diversity (1, 2, or 4 plant species) on soil microeukaryote communities in a temperate grassland experiment using long-amplicon rRNA sequencing. Our results indicate that fertilization generally had a stronger influence on microeukaryote communities than plant species richness. Fertilization altered the community composition of fungi and protists, increased OTU richness by 20.8% and 52.7%, respectively, and shifted community dominance from fungi to protists. Regarding plant diversity, we observed an effect exclusively on the protist community. Changes were primarily explained by increased plant biomass (driven by both fertilization and plant diversity) and by higher soil phosphorus and lower soil pH levels (driven exclusively by fertilization). Regarding life strategies, we observed synergistic treatment effects: fertilization primarily enhanced fungal saprophytes (only richness), fungal animal pathogens, and protist consumers, whereas plant diversity affected phototrophic protists (reduction) and protist animal pathogens (enhancement). Notably, fertilization and plant diversity decline together led to a cumulative increase in fungal plant pathogens. In conclusion, we highlight that fertilisation alone has a significant effect on soil microeukaryotes, while the additional decline in plant diversity affects different soil groups that are not directly affected by fertilisation. This synergistic pattern indicates that fertilization can influence the entire microeukaryote community through direct and indirect mechanisms, with a cumulative enhancement on certain groups, such as plant pathogens.
Project description:We describe a suite of predictive models, coined FASTmC, for non-reference, cost-effective exploration and comparative analysis of context-specific DNA methylation levels. Accurate estimations of true DNA methylation levels can be obtained from as few as several thousand short-reads generated from whole genome bisulfite sequencing. Our models make high-resolution time course or developmental, and large diversity studies practical regardless of species, genome size and availability of a reference genome.