Cigarette smoking is associated with reduced risk of developing Parkinsons disease (PD). To identify genes that interact with nicotine/smoking, we performed hypothesis-free genome-wide experiments in a paraquat-induced Drosophila model and in a case-control study of PD. We demonstrated that nicotine extends life-span in paraquat-treated Drosophila (P=4E-30). Brain tissue from flies treated with combinations of paraquat and nicotine revealed elevated expression of CG14691 with paraquat which was restored with nicotine co-treatment (P(interaction)=2E-11, P(FDR-adjusted)=4E-7). Independently, variants in the 5 region of SV2C, a human ortholog of CG14691, gave the strongest signal for interaction with smoking (P(interaction)=9E-8). The effect of smoking on PD risk varied six-fold by SV2C genotype (P(heterogeneity)=4E-10). Moreover, SV2C variants identified here were associated with SVC2 gene-expression in the HapMap data. Present results suggest synaptic vesicle protein SV2C plays a role in PD pathogenesis, and that the SV2C genotype may be useful for clinical trials of nicotine for treating PD.
A genetic basis for the variable effect of smoking/nicotine on Parkinson's disease.
Sex, Specimen part
View SamplesWe used mammosphere formation assay and label-retention assay as functional cellular approaches to enrich for cells with different degree of cancer stem cell properties in the breast cancer cell line MDA-MB-231 and performed single-cell RNA sequencing Overall design: Single cells from three different populations: 30 cells from G1 cell cycle phase cultured in adherent conditions, 46 cells with low proliferation cultured in non-adherent conditions (mammosphere assasy), 45 cells with high proliferation cultured in non-adherent conditions (mammosphere assay)
Erratum: Identification of Breast Cancer Stem Cell Related Genes Using Functional Cellular Assays Combined With Single-Cell RNA Sequencing in MDA-MB-231 Cells.
Cell line, Subject
View SamplesThe importance of the role of microRNAs in gene expression and disease is well recognized. However, what is less appreciated is that almost half of miRNA genes are organized in polycistronic clusters and are therefore co-expressed. The mir-11~998 cluster consists of two miRNAs, miR-11 and miR-998. Here, we describe a novel layer of regulation that links the processing and expression of miR-998 to the presence of the mir-11 gene. We show that the presence of mir-11 in the pri-miRNA is required for processing by Drosha, and deletion of mir-11 prevents the expression of miR-998. Replacing mir-11 with an unrelated miRNA rescued miR-998 expression in vivo and in vitro, as did expressing miR-998 from a shorter, more canonical miRNA scaffold. The embedded regulation of miR-998 is functionally important because unchecked miR-998 expression in the absence of miR-11 resulted in highly penetrant pleiotropic developmental defects. We further show that this novel regulation of expression of miRNAs within a cluster is not limited to the mir-11~998 cluster and likely reflects the more general cis-regulation of expression of individual miRNAs. Thus, our results reveal a novel layer of regulation within miRNA clusters that tempers the functions of the individual miRNAs. Unlinking their expression has the potential to change the expression of multiple miRNA targets and shift biological response. Overall design: RNA was extracted from Drosophila third instar larval eye discs of animals grown in standard conditions; Illumina HiSeq2000 Next Gen RNA Sequencing was performed, and differential expression of genes was assessed in wild-type vs unchecked miR-998 expression
Novel regulation and functional interaction of polycistronic miRNAs.
Specimen part, Subject
View SamplesExpression of dE2F1 induces proliferation and apoptosis. We sought to perform an unbiased analysis of the effect of co-expression of miR-11
mir-11 limits the proapoptotic function of its host gene, dE2f1.
Specimen part
View SamplesThird instar larval eye discs provide an in vivo model for cell cycle exit studies. Posterior to the Second Mitotic Wave proliferation is absent in a wild type eye disc. Inactivating mutations in tumor suppressor-like genes can lead to genome wide changes in gene expression that allow for inappropriate bypass of cell cycle exit signals posterior to the Second Mitotic Wave.
Cooperation between dE2F1 and Yki/Sd defines a distinct transcriptional program necessary to bypass cell cycle exit.
Specimen part
View SamplesWe used microarrays to identify genes that are differentially expressed in the absence of miR-998 expression.
An intronic microRNA links Rb/E2F and EGFR signaling.
Specimen part
View SamplesThe white adipose tissue (WAT) rapidly loses mass when mice are fed a diet containing trans-10, cis-12 conjugated linoleic acid (t10c12 CLA). A microarray analysis of WAT due to CLA feeding was performed to better define the processes and genes involved. WAT weight decreased by ca. 80% over 17 days of feeding a 0.5% t10c12 CLA diet. The lipid volume decreased by 90% and the number of adipocytes and total cells were reduced by15% and 47%, respectively. Microarray profiling of replicated pools of control and treated mice (n=140) at seven time points over the 17day feeding indicated between 2798 to 4318 genes showed mRNA changes of 2-fold or more. Transcript levels for genes of glucose and fatty acid import or biosynthesis were significantly reduced. A prolific inflammation response was indicated by the 2 to100-fold induction of many cytokine transcripts, including those for IL-6, IL1?, TNF ligands, and CXC family members
Trans-10, cis-12 conjugated linoleic acid causes inflammation and delipidation of white adipose tissue in mice: a microarray and histological analysis.
Age
View SamplesWe characterized the Drosophila third instar eye disc using single cell RNA-seq and labelled the multiple cell populations. The results identified a novel transcriptional switch in photoreceptors relating to axonal projections. We then performed single cell RNA-seq on rbf (Rb) mutants and compared the results to the WT cell populations. This identified a specific cell population only in the Rb mutant tissue. This cell population has an upregulation of HIF1A and glycolitic genes such as Aldolase and Lactate dehydrogenase. As a result these cells produce lactate and undergo apoptosis. We also show this process to be directly regulated by E2F/Dp. The paper uncovers a novel metabolic aspect of Rb/E2F dependent apoptosis. Overall design: examining WT and Rb mutants third instar eye disc using single cell RNA-seq
Single cell RNA-sequencing identifies a metabolic aspect of apoptosis in Rbf mutant.
Specimen part, Subject
View SamplesTrans-10, cis-12 conjugated linoleic acid (t10c12 CLA) causes dramatic reductions in white adipose tissue in mice but has had limited effectiveness in humans. Determination of the signaling pathways involved may lead to better regulation of adiposity. T10c12 CLA was found to activate AMP-activating protein kinase (AMPK), a central regulator of cell metabolism. Compound C, a potent inhibitor of AMPK, prevents many of the typical responses to treatments with t10c12 CLA including the integrated stress response (ISR), the inflammatory response, the reduction in key lipogenic transcription factors, and delipidation. Treatment of adipocytes or mice with t10c12 CLA in conjunction with AMPK activator metformin results in more delipidation than treatment with the individual chemicals. Additionally, the combination showed a reduced inflammatory response relative to a t10c12 CLA treatment alone. The combination of t10c12 CLA and metformin, widely used to treat insulin resistance and Type II diabetes, has potential as a treatment for reducing adiposity in humans.
Conjugated linoleic acid activates AMP-activated protein kinase and reduces adiposity more effectively when used with metformin in mice.
Cell line
View SamplesActivation of the hypoxia inducible transcription factor HIF-alpha and the NF-kappaB pathway promotes inflammation mediated tumor progression.
The hypoxia-inducible transcription factor ZNF395 is controlled by IĸB kinase-signaling and activates genes involved in the innate immune response and cancer.
Cell line, Treatment
View Samples