Project description:We show that the combination of spatially restricted uracil phosphoribosyltransferase (UPRT) expression with 4-thiouracil (4TU) delivery can be used to label and purify cell type specific RNA from intact complex tissues. This method is useful for isolating RNA from cell types that are difficult to isolate by dissection or dissociation methods and should work in any organism where UPRT can be spatially expressed, including mammals and other vertebrates. To confirm that thio-labeled RNA was from UPRT-expressing cells and demonstrate the utility of TU-tagging for cell type-specific RNA isolation, we purified TU-tagged and untagged RNA and compared them using microarrays. We chose to isolate RNA from larval glia, which are present in low number, are highly dispersed, and have a complex cell morphology, making them one of the most difficult cell types to isolate by dissection or dissociation methods. We used reversed polarity (repo)-GAL4 to drive expression of UAS-UPRT specifically in glial cells of the larval brain. We purified TU-tagged and untagged RNA from 72-96h larval brains, and hybridized them to custom Agilent microarrays. We performed two biological replicate experiments.
Project description:Total RNA was extracted from about 10, 1-week or 5-weeks old, entire or dissected (head, legs, wings and ovaries removed) adult flies, using TRIzol reagent (Invitrogen) following manufacturer’s instructions. The following genotypes dedicated for TU-tagging cell - specific transcript isolation were used: Hand>LacZ;HA-UPRT, Hand>MblRNAi;HA-UPRT, Hand>Bru3;HA-UPRT and Hand>960CTG;HA-UPRT
Project description:Studies of neuroepigenetic mechanisms in health and disease are hindered by a lack of approaches to analyze both the transcriptome and epigenome of specific cell types isolated from the complex milieu of the CNS. Cell isolation by cell surface markers is complicated by preparation artifacts, changes in markers with experimental conditions, and lack of specific markers. This study validates a Nuclear Tagging and Translating Ribosome Affinity Purification (NuTRAP) approach with tamoxifen (Tam) inducible cell-type specific cre recombination to allow the parallel interrogation of the epigenome and the transcriptome in astrocytes (Aldh1l1-creERT2) or microglia (Cx3cr1-creERT2). The recombined NuTRAP construct labels, in a cell-type specific manner, nuclei (RanGAP1) with biotin and mCherry, and the ribosomes (L10a) with EGFP, enabling INTACT isolation of DNA and TRAP isolation of RNA. Validation experiments by flow cytometry and imaging demonstrate cell-type specific induction of the NuTRAP construct. Transcriptomic studies demonstrate isolation of highly enriched RNA by TRAP and oxidative bisulfite studies of INTACT-isolated DNA demonstrate differential DNA modification patterns in microglia and astrocytes. LPS administration in Cx3cr1 NuTRAP mice demonstrates that microglia-specific transcriptome and epigenome changes are revealed that cannot be detected with tissue-level samples. These experiments demonstrate that the NuTRAP approach can be applied to CNS cell populations and that INTACT approaches can be used to study DNA modifications. These results also provide an approach for generation and validation of NuTRAP neuroscience models crossed to any relevant cell-type specific cre line.
Project description:Studies of neuroepigenetic mechanisms in health and disease are hindered by a lack of approaches to analyze both the transcriptome and epigenome of specific cell types isolated from the complex milieu of the CNS. Cell isolation by cell surface markers is complicated by preparation artifacts, changes in markers with experimental conditions, and lack of specific markers. This study validates a Nuclear Tagging and Translating Ribosome Affinity Purification (NuTRAP) approach with tamoxifen (Tam) inducible cell-type specific cre recombination to allow the parallel interrogation of the epigenome and the transcriptome in astrocytes (Aldh1l1-creERT2) or microglia (Cx3cr1-creERT2). The recombined NuTRAP construct labels, in a cell-type specific manner, nuclei (RanGAP1) with biotin and mCherry, and the ribosomes (L10a) with EGFP, enabling INTACT isolation of DNA and TRAP isolation of RNA. Validation experiments by flow cytometry and imaging demonstrate cell-type specific induction of the NuTRAP construct. Transcriptomic studies demonstrate isolation of highly enriched RNA by TRAP and oxidative bisulfite studies of INTACT-isolated DNA demonstrate differential DNA modification patterns in microglia and astrocytes. LPS administration in Cx3cr1 NuTRAP mice demonstrates that microglia-specific transcriptome and epigenome changes are revealed that cannot be detected with tissue-level samples. These experiments demonstrate that the NuTRAP approach can be applied to CNS cell populations and that INTACT approaches can be used to study DNA modifications. These results also provide an approach for generation and validation of NuTRAP neuroscience models crossed to any relevant cell-type specific cre line.
Project description:Studies of neuroepigenetic mechanisms in health and disease are hindered by a lack of approaches to analyze both the transcriptome and epigenome of specific cell types isolated from the complex milieu of the CNS. Cell isolation by cell surface markers is complicated by preparation artifacts, changes in markers with experimental conditions, and lack of specific markers. This study validates a Nuclear Tagging and Translating Ribosome Affinity Purification (NuTRAP) approach with tamoxifen (Tam) inducible cell-type specific cre recombination to allow the parallel interrogation of the epigenome and the transcriptome in astrocytes (Aldh1l1-creERT2) or microglia (Cx3cr1-creERT2). The recombined NuTRAP construct labels, in a cell-type specific manner, nuclei (RanGAP1) with biotin and mCherry, and the ribosomes (L10a) with EGFP, enabling INTACT isolation of DNA and TRAP isolation of RNA. Validation experiments by flow cytometry and imaging demonstrate cell-type specific induction of the NuTRAP construct. Transcriptomic studies demonstrate isolation of highly enriched RNA by TRAP and oxidative bisulfite studies of INTACT-isolated DNA demonstrate differential DNA modification patterns in microglia and astrocytes. LPS administration in Cx3cr1 NuTRAP mice demonstrates that microglia-specific transcriptome and epigenome changes are revealed that cannot be detected with tissue-level samples. These experiments demonstrate that the NuTRAP approach can be applied to CNS cell populations and that INTACT approaches can be used to study DNA modifications. These results also provide an approach for generation and validation of NuTRAP neuroscience models crossed to any relevant cell-type specific cre line.
Project description:Studies of neuroepigenetic mechanisms in health and disease are hindered by a lack of approaches to analyze both the transcriptome and epigenome of specific cell types isolated from the complex milieu of the CNS. Cell isolation by cell surface markers is complicated by preparation artifacts, changes in markers with experimental conditions, and lack of specific markers. This study validates a Nuclear Tagging and Translating Ribosome Affinity Purification (NuTRAP) approach with tamoxifen (Tam) inducible cell-type specific cre recombination to allow the parallel interrogation of the epigenome and the transcriptome in astrocytes (Aldh1l1-creERT2) or microglia (Cx3cr1-creERT2). The recombined NuTRAP construct labels, in a cell-type specific manner, nuclei (RanGAP1) with biotin and mCherry, and the ribosomes (L10a) with EGFP, enabling INTACT isolation of DNA and TRAP isolation of RNA. Validation experiments by flow cytometry and imaging demonstrate cell-type specific induction of the NuTRAP construct. Transcriptomic studies demonstrate isolation of highly enriched RNA by TRAP and oxidative bisulfite studies of INTACT-isolated DNA demonstrate differential DNA modification patterns in microglia and astrocytes. LPS administration in Cx3cr1 NuTRAP mice demonstrates that microglia-specific transcriptome and epigenome changes are revealed that cannot be detected with tissue-level samples. These experiments demonstrate that the NuTRAP approach can be applied to CNS cell populations and that INTACT approaches can be used to study DNA modifications. These results also provide an approach for generation and validation of NuTRAP neuroscience models crossed to any relevant cell-type specific cre line.
Project description:To investigate gene expression changes in Drosophila head tissues during social isolation, we performed RNA-sequencing on fruit fly head samples obtained from male flies that have been group-reared for 7 days (Grp), isolated (single-housed) for 7 days (Iso7) and isolated (single-housed) for only 1 day (Iso1). Using differential gene expression analysis, we found a group of candidate genes that are specific to chronic social isolation: they exhibited significant gene expression change in both comparisons of “Grp vs Iso1” and “Iso1 vs Iso7”.