Project description:The aim of this study was to identify umbilical cord microRNA (miRNA) associated with catch-up growth in SGA infants. miRCURY LNA™ Universal RT microRNA PCR Human Panel I+II (Exiqon) were used to study the miRNA profile in umbilical cord tissue of 5 SGA infants with catch-up (SGA-CU), 5 SGA infants without catch-up (SGA-nonCU) and 5 control infants (appropriate-for-gestational-age, AGA). Catch-up differentially expressed miRNA were studied and validated in a larger cohort.
Project description:We describe here a sensitive and novel method of identifying endogenous DNA-DNA interactions. Capture of Associated Targets on CHromatin (CATCH) uses efficient capture and enrichment of specific genomic loci of interest through hybridization and subsequent purification via complementary biotinylated oligonucleotide. The CATCH assay requires no enzymatic digestion or ligation, requires little starting material, provides high quality data, has excellent reproducibility and is completed in less than 24 hours. Efficacy is demonstrated through capture of three disparate loci, which demonstrate unique subsets of long-distance chromatin interactions enriched for both enhancer marks and estrogen receptor binding sites. In each experiment, CATCH-seq peaks representing long-distance chromatin interactions were centered near the TSS of genes, and critically, the genes identified as physically interacting are shown to be transcriptionally co-expressed. These interactions could potentially create transcriptional hubs for the regulation of gene expression programs.
Project description:Direct measurement of nucleosome turnover dynamics by using co-translational incorporation of the methionine (Met) surrogate azidohomoalaine (Aha) into proteins and subsequent ligation of biotin to Aha-containing proteins through the [3+2] cycloaddition reaction between the azide group of Aha and an alkyne linked to biotin. To measure turnover rates, we treat cells briefly with Aha, couple biotin to nucleosomes containing newly incorporated histones, affinity purify with strepavidin, wash stringently to remove non-histone proteins and H2A/H2B dimers, and analyze the affinity-purified DNA using tiling microarrays. We call this strategy 'CATCH-IT' for Covalent Attachment of Tags to Capture Histones and Identify Turnover. Keywords: Chromatin affinity-purification on microarray
Project description:We report that after cancer cells are exposed to a transient pulse (5h) of the pro-inflammatory cytokine IFNγ, they continue up-regulating genes in the antigen presentation pathway for days after abrogation of the original signal. We discovered that a new mechanism of cell-to-cell communication, cytokine catch-and-release, explains this surprising result.
Project description:Direct measurement of nucleosome turnover dynamics by using co-translational incorporation of the methionine (Met) surrogate azidohomoalaine (Aha) into proteins and subsequent ligation of biotin to Aha-containing proteins through the [3+2] cycloaddition reaction between the azide group of Aha and an alkyne linked to biotin. To measure turnover rates, we treat cells briefly with Aha, couple biotin to nucleosomes containing newly incorporated histones, affinity purify with strepavidin, wash stringently to remove non-histone proteins and H2A/H2B dimers, and analyze the affinity-purified DNA using tiling microarrays. We call this strategy 'CATCH-IT' for Covalent Attachment of Tags to Capture Histones and Identify Turnover. Keywords: Chromatin affinity-purification on microarray All experiments were done using strepavidin pulldown DNA cohybridized with total input DNA to the same array. Two channels per array, Cy5 and Cy3, were used in each experiment.