XL-MS analysis of AMPK activation loop accessibility regulation.
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Orbitrap Fusion Lumos
ORGANISM(S): Homo Sapiens (human)
SUBMITTER: 
Timothy Strutzenberg
LAB HEAD: Patrick R. Griffin
PROVIDER: PXD019017 | Pride | 2021-07-08
REPOSITORIES: Pride
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| 20200228_TRY_AMPK_ATPgS_REP1.raw | Raw | |||
| 20200228_TRY_AMPK_ATPgS_REP2.raw | Raw | |||
| 20200228_TRY_AMPK_ATPgS_REP3.raw | Raw | |||
| 20200228_TRY_AMPK_NoXL_REP1.raw | Raw | |||
| 20200228_TRY_AMPK_NoXL_REP2.raw | Raw |
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Project description:Identification and characterization of HP1BP3 (a human histone H1 homologue) as a novel chromatin retention factor essential for the co-transcriptional processing of pri-miRNA. We generated BAC transgenic cells at 80% confluency (~1x107) were cross-linked with 1% formaldehyde for 10 minutes at 37°C, and quenched with 125 mM glycine at room temperature for 5 minutes. The fixed cells were washed twice with cold PBS, scraped, and transferred into 1 ml PBS containing protease inhibitors (Roche). After centrifugation at 700 g for 4 minutes at 4°C, the cell pellets were resuspended in 100 μl ChIP lysis buffer (1% SDS, 10 mM EDTA, 50 mM Tris-HCl [pH 8.1] with protease inhibitors) and sonicated at 4°C with a Bioruptor (Diagenode) (30 seconds ON and 30 seconds OFF at highest power for 15 minutes). The sheared chromatin with a fragment length of ~200 â 600 bp) was centrifuged at 20,000 g for 15 minutes at 4°C). 100 μl of the supernatant was used for ChIP or as input. A 1:10 dilution of the solubilized chromatin in ChIP dilution buffer (0.01% SDS, 1.1% Triton X-100, 1.2 mM EDTA, 167 mM NaCl 16.7 mM Tris-HCl [pH 8.1]) was incubated at 4°C overnight with 6 μg/ml of a goat anti-GFP (raised against His-tagged full-length eGFP and affinity-purified with GST-tagged full-length eGFP). Immunoprecipitation was carried out by incubating with 40 μl pre-cleared Protein G Sepharose beads (Amersham Bioscience) for 1 hour at 4°C, followed by five washes for 10 minutes with 1ml of the following buffers: Buffer I: 0.1% SDS, 1% Triton X-100, 2 mM EDTA, 20 mM Tris-HCl [pH 8.1], 150 mM NaCl; Buffer II: 0.1% SDS, 1% Triton X-100, 2 mM EDTA, 20 mM Tris-HCl [pH 8.1], 500 mM NaCl; Buffer III: 0.25 M LiCl, 1% NP-40, 1% deoxycholate, 1 mM EDTA, 10 mM Tris-HCl [pH 8.1]; twice with TE buffer [pH 8.0]. Elution from the beads was performed twice with 100 μl ChIP elution buffer (1% SDS, 0.1 M NaHCO3) at room temperature (RT) for 15 minutes. Protein-DNA complexes were de-crosslinked by heating at 65°C in 192 mM NaCl for 16 hours. DNA fragments were purified using QiaQuick PCR Purification kit (QIAGEN) and eluted into 30 μl H2O according to the manufacturerâs protocol after treatment with RNase A and Proteinase K.
2016-07-24 | E-GEOD-77854 | biostudies-arrayexpress
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2010-06-05 | E-GEOD-404 | biostudies-arrayexpress
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Project description:gDNA was estracted and digested with cocktail of restrict enzymes MseI, DdeI, AluI, MboI, incubated at 37°C for 6 h. After purified by phenol/chloroform extraction, fragmented DNA was resuspended by TE, and quantified by Qubit 3.0 (Invitrogen). For each sample, 20 μg input DNA was immunoprecipitated overnight at 4°C in a shaker, with 1× DRIP binding buffer (10 mM NaPO4 pH 7.0, 140 mM NaCl, 0.05% Triton X-100) and 10 μg S9.6 antibody (ATCC, HB-8730). After adding 50 μl Dynabeads Protein G (Invitrogen, 10004D) and incubated for 4 h, the beads with antibody were washed by 1× DRIP binding buffer for 4 times at room temperature, each wash takes 10 min. Added 250 μl elution buffer (50 mM Tris pH 8.0, 10 mM EDTA, 0.5% SDS) and 5 U Proteinase K to beads/antibody complexes, incubated for 40 min in an Eppendorf ThermoMixer at 55°C, 1,000 rpm. Purified by phenol/chloroform extraction, and moved supernatant to a new tube, followed by adding 1/10 volume 3 M NaAc, 1 μl GlycoBlue (Invitrogen) and 1 volume isopropanol, precipitated at -20°C for 3 h and then centrifuged. After washed by 70% ethanol and dried, the DRIPed DNA pellet was resuspended by 75 μl low EDTA TE buffer (10 mM Tris-HCl 8.0, 0.1 mM EDTA). NGS libraries were constructed using Accel-NGS® 1S Plus DNA Library Kit (Swift Biosciences).
2019-10-15 | GSE134101 | GEO
Project description:A control group consisting of nine C57/BL/6J mice was maintained on a normal diet consisting of Purina Rodent Chow (Harlan Teklad, catalog #5008, 6.5% fat, 49% carbohydrate, 23% protein, 3.5 kcal/ g). The experimental group consisted of nine mice grown on a specialty high-fat diet (Harlan Teklad, catalog #TD88137, 42.16% fat, 42.81% carbohydrate, 15.02% protein, 4.53 kcal/ g). Mice were maintained for ten weeks on their respective diets in a controlled environment with standard light and feeding schedule. Two days before tissue harvest, the experimental group on the high-fat diet was divided into one group of five and one group of four mice. The first group continued on the high-fat diet for the final two days, while the second group fasted. Mouse weights were recorded two days prior, and the day of tissue harvest. At the end of the fasting period liver tissue samples were harvested from each mouse. RNA was purified from the liver tissue samples. Each tissue was homogenized in 1 mL of STAT-60 (Tel-Test, Inc., Friendswood, TX) and the homogenate was mixed with 200 uL of chloroform. The aqueous phase was removed, and mixed with 500 uL of isopropanol to precipitate the RNA. The resulting RNA pellet was washed with 500 uL of 70% ethanol and allowed to air dry. The pellet was dissolved in RNase free water (Ambion, TX), quantified by UV spectroscopy, and stored at -80C. Total RNA control samples (Universal Mouse Reference RNA, catalog # 740100, Stratagene) were labeled using Cy3 dCTP (Perkin-Elmer), and liver total RNA experimental samples were labeled using Cy5 dCTP (Perkin-Elmer) during reverse transcription. For reverse transcription 10 ug of total RNA was mixed with 2 uL of 10X Cy-labeled dCTP, 2 uL of 100 mM DTT (Invitrogen), 4 uL of 5X First Strand Buffer (Invitrogen), 2 uL of a dNTP mixture containing 5 mM dGTP, dATP, dTTP and 2 mM dCTP (Invitrogen), 2 uL of 0.5 mg/ mL oligo-dT18-20 (Invitrogen), and 2 uL of Superscript II reverse transcriptase (Invitrogen). The control RNA samples were additionally mixed with 2 uL of random hexamers. The reaction mixtures were incubated at 42 C for two hours. After the reverse transcription reactions, the RNA templates were degraded by addition of 2 uL of 1 N NaOH and incubation at 65 C for 10 minutes. The alkaline conditions were neutralized by addition of 2 uL of 1 N HCl. Liver cDNA samples were then mixed with a control cDNA sample, and the mixtures were cleaned using a QIAquick Nucleotide Removal kit (Qiagen) as described by the manufacturer's instructions. The cleaned samples were concentrated in a speed vacufuge (Eppendorf) for 20 minutes at 65 C, and were dissolved in 32 uL of prewarmed hybridization buffer (Clontech Laboratories), quantified, and hybridized to prepared oligonucleotide microarrays. Hybridization occurred overnight at 55 C using Corning hybridization chambers. The following day the arrays were washed in Glass Hybridization Wash Solution (Clontech Laboratories), then in 1X SSC, and finally in 0.1X SSC. The arrays were dried by centrifugation and scanned using a GenePix 4000B scanner (Axon Instruments). The resulting data was downloaded and formatted in Excel (Microsoft), and analyzed using Matlab (The MathWorks, Inc.). Microarrays were prepared using GAPS glass slides (Corning), and a Virtek arrayer (Bio-Rad). Arrays contained 16,847 features, printed from a synthesized oligonucleotide mouse library (Operon). The library was suspended in 3X SSC, centrifuged, and loaded into the arrayer. Arrays were printed at approximately 50% humidity. Once printed, the probes were crosslinked using a UV Stratalinker (Stratagene). The slides were then blocked for 15 minutes in a 250 mL mixture containing 15.7 g/ L succinic anhydride (Fluka AG), 239 mL 1-methyl-2-pyrrolidinone (EM Science), and 10.7 mL of 1 M boric acid (Fisher), pH 8.0. They were cleaned by rinsing twice in 250 mL of milli-Q water, followed by 250 mL of 95% ethanol (Pharmco Products). After blocking, they were dried using filtered air and stored in the dark at room temperature. In this experiment the gene expression data of the control mice is given by samples GSM6592, GSM6593, GSM6594, and GSM6595. The gene expression data of the high-fat mice is given by samples GSM6599, GSM6600, GSM6601, and GSM6602. The gene expression data of the fasted mice is given by samples GSM6596, GSM6597, and GSM6598. Keywords = mouse, liver, energy homeostasis, gene expression, microarrays Keywords: repeat sample
2003-05-16 | GSE432 | GEO
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2014-09-25 | E-GEOD-58382 | biostudies-arrayexpress
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2004-02-11 | GSE1031 | GEO
Project description:Purpose: Investigation of genome-wide changes in R-loop levels after knockdown of DDX41 U2OS cells in comparison to a control knockdown. Method: Concanavalin A-coated beads were activated in Binding Buffer (20 mM Hepes-KOH pH 7.9, 10 mM KCl, 1mM CaCl2, 1 mM MnCl2). 5*105 U2OS cells were washed twice with Wash Buffer (Hepes-NaOH pH7.5, 150 mM NaCl, 0.5 mM Spermidine, 1 mM protease inhibitor) at room temperature and afterwards immobilized on the activated beads in 50 µl Wash Buffer containing 0.05% Digitonin. Either pA-MNase or RHΔ-MNase were added to the cells overnight at 4°C on a rotating wheel. After three washes with Wash Buffer containing 0.05% Digitonin, samples resuspended in 100 µl Dig-Wash-Buffer were equilibrated on ice. Activity of the MNase was triggered by adding 2mM CaCl2 to the samples for 30 minutes. 2x Stop Buffer (68 µl 5M NaCl, 40 µl 0.5 M EDTA, 20 µl 0.2 M EGTA, 10 µl 5% digitonin, 5 µl 10mg/ml RnaseA, 20 pg/ml spike-in Drosophila DNA (Active Motif)) was mixed with the samples to stop the reaction. Chromatin fragments were released by incubating the samples for 20 minutes at 37°C and centrifugation at 16.000×g for 10 minutes at 4°C. Supernatants were incubated at 70°C in the presence of 0.1% SDS and 5 µg proteinase K. Before library preparation, the DNA was recovered by phenol-chloroform extraction Results: We were able to map R-loop dynamics genome-wide in U2OS cells in biological triplicates. MapR signal was significantly increased around the transcription start site in the absence of DDX41 and decreased after treatment with ActinomycinD.
2021-05-04 | GSE168170 | GEO