Transcripts enriched in microsome fraction in ribosome-independent manner
Ontology highlight
ABSTRACT: To identify the transcripts fractionated into microsome fraction in ribosome-independent manner, we isolate rough microsome fraction by sucrose density gradient ultracengrifugation, then the rough microsome fraction is centrifugated following treatment with puromycine and EDTA in high-salt buffer to remove ribosomes. The pellet and surpernatant are named naked microsome fraction (NM) and stripped ribosome fraction (SR), respectively. By calculating the ratio of the level of each mRNA in NM and SR, we identify the enriched transcripts in NM.
Project description:Heathly naked mole-rats kept under normal housing conditions harbor either a small or enlarged spleen. The aim of the study is to compare RNAseq of naked mole-rat (NM-R) small and enlarged spleens between them and to compare them with RNAseq of mouse spleen.
Project description:The goals of this study are to discover the RNAs associated with the condensed chromosomes during mitosis. RNA from the soluble and pellet fraction of the lysed mitotic HCT116 cells were extracted, RNA profiles of soluble and pellet RNA were generated by deep sequencing, using MGISEQ2000. The sequence reads that passed quality filters were analyzed by STAR (v2.7.8a). Using an optimized data analysis workflow, we found that the pre-rRNAs were significantly enriched in the pellet fraction of the mitotic HCT116 cells.
Project description:10 million cells were used for each sample. The cells were pre-treated with or without Doxorubicin (2µM for 4h) before collection and washed with ice-cold 1 × PBS. The nuclei pellet was further fractionated into nucleoplasmic fraction (supernatant) and chromatin pellet by using MWS buffer. All the buffers above were supplemented with protease inhibitor cocktail (Thermo Fisher Scientific) and Ribonuclease Inhibitors (Promega). The RNA precipitation solution (RPS) buffer was added into the cytoplasmic fraction and nucleoplasmic fraction immediately and each fraction was stored at -20°C for at least 1h. The two fractions were centrifuged and the resulting pellets were washed with 75% ethanol. All the pellets from the chromatin fraction, nucleoplasmic fraction and cytoplasmic fraction were added with 1mL TRIzol (Invitrogen) to extract RNA. The RNA pellet in TRIzol was fully dissolved by adding EDTA to the final concentration of 5mM and heat it to 65°C. The resulting RNAs from each fraction were subjected to DNase I (Sigma-Aldrich) treatment followed by phenol/chloroform extraction to remove any contaminant DNA. The RNA pellets of each fraction were then dissolved in equal volumes of RNase-free water and used for snoRNA qRT-PCR analyses.
Project description:Local translation in neurons is mediated in part by the reactivation of stalled polysomes. However, the mechanism for stalling of the polysomes is not understood. Stalled polysomes may be enriched in neuronal RNA granules defined by dense collections of compacted ribosomes found in the pellet of sucrose gradients used to separate polysomes from monosomes. We find that this fraction, isolated from P5 rat brains of both sexes, is enriched in proteins implicated in stalled polysome function, such as the fragile X mental retardation protein (FMRP) and Up-frameshift mutation 1 homolog (UPF1). Ribosome profiling of this fraction showed an abundance of footprint reads derived from mRNAs of cytoskeletal proteins implicated in neuronal development, as well as an enrichment of footprint reads on RNA binding proteins. The footprint reads were extended than those usually found in ribosome profiling studies on the 3’end and were found in reproducible peaks in the mRNAs with a bias towards the first half of the message. These footprint reads were enriched in motifs previously associated with mRNAs cross-linked to FMRP in vivo, independently linking the ribosomes in the sedimented pellet to the ribosomes associated with FMRP in the cell. The data supports a model in which specific sequences in mRNAs act to stall translation elongation in neurons, attracting FMRP and beginning a process where stalled ribosomes are packaged and transported in RNA granules.
Project description:Background: The phospholamban (PLN) p.Arg14del mutation belongs to the established causes of dilated cardiomyopathy, with the molecular disease mechanisms incompletely understood. We used human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes, CRISPR/Cas9 gene editing and patient heart samples to investigate the molecular pathomechanisms of PLN p.Arg14del cardiomyopathy. Methods and results: Patient dermal fibroblasts carrying the PLN p.Arg14del mutation were reprogrammed into hiPSC, isogenic controls were established by CRISPR/Cas9. Cells were differentiated into cardiomyocytes and characterized in 2D and 3D-engineered heart tissue (EHT) format. Mutant cardiomyocytes revealed significantly prolonged Ca2+ transient decay time, Ca2+-load dependent irregular beating pattern and lower peak force compared to isogenic controls. While this data support the reported super-inhibitory effect of PLN p.Arg14del on the sarcoplasmic/endoplasmic reticulum Ca2+ ATPase, an unchanged SR Ca2+ content argued against disturbed SR Ca2+ cycling as the sole cause of contractile dysfunction. Label-free proteomic analysis of p.Arg14del EHTs revealed less endoplasmic reticulum (ER), ribosomal and mitochondrial proteins. Electron microscopy showed dilation of the rough ER, large lipid droplets in close association with mitochondria and reduced mitochondrial number. Follow-up experiments confirmed impairment of the rough ER/mitochondria compartment and enhanced oxidative stress in PLN p.Arg14del. Relevance for human disease was demonstrated by immunohistochemistry of human heart samples. PLN p.Arg14del end-stage heart failure samples revealed perinuclear aggregates positive for ER marker proteins and oxidative stress in comparison to ischemic heart failure - and non-failing donor heart samples. Surprisingly, transduction of PLN p.Arg14del EHTs with the Ca2+ binding protein GCaMP6f reversed the contractile, molecular and morphological disease phenotype. Conclusion: This study identified impairment of the rough ER/mitochondria compartment without SR dysfunction as a novel disease mechanism underlying PLN p.Arg14del cardiomyopathy. The pathology was improved by Ca2+-scavenging, suggesting impaired local Ca2+ cycling as an important disease culprit.
Project description:In total 8,736,191 reads from IP fraction and 9,958,984 reads from Wash fraction uniquely mapped to the mouse genome (mm9). Settings for enrichment analysis: maxSpacing=500; minHits=20; minPeakHits=6; minRatio=3. 4,701 regions have been identified as enriched in the IP fraction. In order to get a rough idea of false discovery rate (FDR), enrichment analysis using Wash fraction as test and IP fraction as control was performed, 15 regions was found. This suggests that the FDR likely is around 0.3%. Keywords: Epigenetics
Project description:In total 8,736,191 reads from IP fraction and 9,958,984 reads from Wash fraction uniquely mapped to the mouse genome (mm9). Settings for enrichment analysis: maxSpacing=500; minHits=20; minPeakHits=6; minRatio=3. 4,701 regions have been identified as enriched in the IP fraction. In order to get a rough idea of false discovery rate (FDR), enrichment analysis using Wash fraction as test and IP fraction as control was performed, 15 regions was found. This suggests that the FDR likely is around 0.3%. Keywords: Epigenetics Examination of PCL2 enrichment in mouse ESCs.
Project description:Our data suggest that all SR proteins contribute to mRNA export via NXF1. To identify endogenous export targets we depleted all seven SR proteins individually from P19 WT cells prepared cytoplasmic fractions. We sequenced the cytoplasmic fraction and as a control whole celll RNA from the identical sample.
Project description:Our data suggest that all SR proteins contribute to mRNA export via NXF1. To identify endogenous export targets we depleted all seven SR proteins individually from P19 WT cells prepared cytoplasmic fractions. We sequenced the cytoplasmic fraction and as a control whole celll RNA from the identical sample. Knockdown of seven SR Proteins plus control, total RNA and cytoplasmic RNA, polyA+ enriched, 2 biological replicates per condition, 2 technical replicates per condition