Project description:Many MS2 spectra in bottom-up proteomics experiments remain unassigned. To improve proteome coverage, we applied the half decimal place rule (HDPR) to remove non-peptidic molecules. The HDPR considers the ratio of the first digit after the decimal point to the full molecular mass and results in a relatively small permitted mass window for most peptides. Although the HDPR has been described previously, it has never been integrated into an acquisition strategy using high resolution mass spectrometers. The HDPR was applied to three technical replicates of an in-solution tryptic digest of HeLa cells which were analysed by LC-MS using a Q Exactive mass spectrometer.
Project description:Many MS2 spectra in bottom-up proteomics experiments remain unassigned. To improve proteome coverage, we applied the half decimal place rule (HDPR) to remove non-peptidic molecules. The HDPR considers the ratio of the first digit after the decimal point to the full molecular mass and results in a relatively small permitted mass window for most peptides. Although the HDPR has been described previously, it has never been integrated into an acquisition strategy using high resolution mass spectrometers. The HDPR was applied to three technical replicates of an in-solution tryptic digest of HeLa cells which were analysed by LC-MS using a Q Exactive mass spectrometer.
Project description:Many MS2 spectra in bottom-up proteomics experiments remain unassigned. To improve proteome coverage, we applied the half decimal place rule (HDPR) to remove non-peptidic molecules. The HDPR considers the ratio of the first digit after the decimal point to the full molecular mass and results in a relatively small permitted mass window for most peptides. Although the HDPR has been described previously, it has never been integrated into an acquisition strategy using high resolution mass spectrometers. The HDPR was applied to three technical replicates of an in-solution tryptic digest of HeLa cells which were analysed by LC-MS using a Q Exactive mass spectrometer.
Project description:Microbome place model is a Named Entity Recognition (NER) model that identifies and annotates the geographical location of microbiome samples in texts. This is the final model version used to annotate metagenomics publications in Europe PMC and enrich metagenomics studies in MGnify with place metadata from literature. For more information, please refer to the following blogs: http://blog.europepmc.org/2020/11/europe-pmc-publications-metagenomics-annotations.html https://www.ebi.ac.uk/about/news/service-news/enriched-metadata-fields-mgnify-based-text-mining-associated-publications
Project description:Substance use disorder emerges in a small proportion of drug users and has the characteristics of a chronic relapsing pathology. The objective of our study was to demonstrate and characterize the variability in the expression of the reinforcing effects of cocaine in the conditioned place preference (CPP) paradigm. An unbiased cocaine-CPP paradigm in Sprague-Dawley rats with an extinction period of 12 days and reinstatement was conducted. We developed a statistical model to distinguish rats that express or do not express cocaine-induced place preference. Two groups of rats were identified: rats that did express reinforcing effects (CPP expression (CPPE), score > 102 s) and rats that did not (no CPP expression (nCPPE), score between −85 and 59 s). These two groups did not show significant differences in a battery of behavioral tests. To identify differentially expressed genes in the CPPE and nCPPE groups, we performed a whole-transcriptome RNA-sequencing analysis in the nucleus accumbens (Nac) 24 h after the CPP test. Four immediate early genes (Fos, Egr2, Nr4a1 and Zbtb37) were differentially expressed in the Nac of CPPE rats after CPP memory retrieval. Variability in cocaine-induced place preference persisted in the CPPE and nCPPE groups after the extinction and reinstatement phases. Transcriptomic differences observed after reinstatement were distinct from those observed immediately after CPP memory retrieval. These new findings provide insights into the identification of mechanisms underlying interindividual variability in the response to cocaine's reinforcing effects.
Project description:Drug-induced alterations in gene expression play an important role in the development of addictive behavior. Methionine has been proven to inhibit addictive behaviors of cocaine dependence. However, the mechanisms underlying how methionine use corresponds to drug-induced behaviors still remain unclear. We performed mRNA and miRNA high-throughput sequencing of the prefrontal cortex in a mouse model of cocaine CPP combined with L-methionine in order to identify L-methionine target miRNAs and genes that participate in the cocaine conditioned place preference (CPP). We found that the L-methionine inhibits cocaine CPP. Sequencing data analysis showed that L-methionine down-regulates genes enriched in the Glutamatergic Synapse pathways and significantly reversed the cocaine-induced expression changes of the substance dependence pathways (Morphine addiction and Nicotine addiction) and the neurotransmitter synapse pathways (Glutamatergic Synapse, Cholinergic Synapse and GABAergic Synapse). Furthermore, the Glutamatergic synapse was either overlapped between DEGs with DEGs-miRNA induced by cocaine CPP, or with the MET effects on cocaine CPP. Nineteen targeted genes were investigated and five were identified (Gria4, Grid1, Grik4, Grik5 and Grin3a) to belong to iGluR family. Interestingly, there were several miRNAs that had the same sequence which targets the iGluR family: Mmu-miR-30e-50p and mmu-miR-380-5p share UUGAC motif and targets Grik4; mmu-miR-6940-3p and mmu-miR-212-5p both share UGGCU motif which targets Gria4 and Grid1 respectively. Thus, we demonstrated the efficacy of L-methionine in counteracting the effects of cocaine CPP and identified specific genes of synaptic plasticity pathways, especially the Glutamatergic synapse pathway, which is modulated by L-methionine in response to cocaine dependence.
Project description:Substance use disorder emerges in a small proportion of drug users and has the characteristics of a chronic relapsing pathology. The objective of our study was to demonstrate and characterize the variability in the expression of the reinforcing effects of cocaine in the conditioned place preference (CPP) paradigm. An unbiased cocaine-CPP paradigm in Sprague-Dawley rats with an extinction period of 12 days and reinstatement was conducted. We developed a statistical model to distinguish rats that express or do not express cocaine-induced place preference. Two groups of rats were identified: rats that did express reinforcing effects (CPP expression (CPPE), score > 102 s) and rats that did not (no CPP expression (nCPPE), score between −85 and 59 s). These two groups did not show significant differences in a battery of behavioral tests. To identify differentially expressed genes in the CPPE and nCPPE groups, we performed a whole-transcriptome RNA-sequencing analysis in the nucleus accumbens (Nac) 24 h after the CPP test. Four immediate early genes (Fos, Egr2, Nr4a1 and Zbtb37) were differentially expressed in the Nac of CPPE rats after CPP memory retrieval. Variability in cocaine-induced place preference persisted in the CPPE and nCPPE groups after the extinction and reinstatement phases. Transcriptomic differences observed after reinstatement were distinct from those observed immediately after CPP memory retrieval. These new findings provide insights into the identification of mechanisms underlying interindividual variability in the response to cocaine's reinforcing effects.