Alpha-synuclein is an abundant protein implicated in synaptic function and plasticity, but the molecular mechanism of its action is not understood. Missense mutations and gene duplication/triplication events result in Parkinson's disease, a neurodegenerative disorder of old age with impaired movement and emotion control. Here, we systematically investigated the striatal as well as the cerebellar transcriptome profile of alpha-synuclein-deficient mice via a genome-wide microarray survey in order to gain hypothesis-free molecular insights into the physiological function of alpha-synuclein. A genotype-dependent, specific and strong downregulation of forkhead box P1 (Foxp1) transcript levels was observed in all brain regions from postnatal age until old age and could be validated by qPCR. In view of the co-localization and heterodimer formation of FOXP1 with FOXP2, a transcription factor with a well established role for vocalization, and the reported regulation of both alpha-synuclein and FOXP2 expression during avian song learning, we performed a detailed assessment of mouse movements and vocalizations in the postnatal period. While there was no difference in isolation-induced behavioral activity in these animals, the alpha-synuclein-deficient mice exhibited an increased production of isolation-induced ultrasonic vocalizations (USVs). This phenotype might also reflect the reduced expression of the anxiety-related GABA-A receptor subunit gamma 2 (Gabrg2) we observed. Taken together, we identified an early behavioral consequence of alpha-synuclein deficiency and accompanying molecular changes, which supports the notion that the neural connectivity of sound or emotion control systems is affected.
Alpha-synuclein deficiency affects brain Foxp1 expression and ultrasonic vocalization.
Age, Specimen part
View SamplesEstablishing reliable biomarkers for assessing and validating clinical diagnosis at early prodromal stages of Parkinson’s disease is crucial for developing therapies to slow or halt disease progression. Here, we present the largest study to date using whole blood gene expression profiling from over 500 individuals to identify an 87-gene blood-based signature. Our gene signature effectively differentiates between idiopathic PD patients and controls in both a validation cohort and an independent test cohort, and further highlights mitochondrial metabolism and ubiquitination/proteasomal degradation as potential pathways disrupted in Parkinson’s disease.
Analysis of blood-based gene expression in idiopathic Parkinson disease.
Sex, Specimen part, Subject
View SamplesMethyl tert-butyl ether (MTBE) has been shown to target developing vasculature in piscine and mammalian model systems. In the zebrafish, MTBE induces vascular lesions throughout development. These lesions result from exposure to MTBE at an early stage in development (6-somites to Prim-5 stages). During this time period, transcript levels of vegfa, vegfc, and vegfr1 were significantly decreased in embryos exposed to 5 mM MTBE.
Manipulation of the HIF-Vegf pathway rescues methyl tert-butyl ether (MTBE)-induced vascular lesions.
Specimen part
View SamplesScaffold proteins regulate intracellular MAP kinase signaling by providing critical spatial and temporal specificity. We have shown previously that the scaffold protein MEK1 partner (MP1) is localized to late endosomes by the adaptor protein p14. Using conditional gene disruption of p14 in livers of mice we analysed protein and transcript signatures in tissue samples. Further biological network analysis predicted that the differentially expressed transcripts and proteins are involved in cell cycle progression and regulation of cellular proliferation. Although some of the here identified signatures were previously linked to phospho-ERK activity, most of them were novel targets of late endosomal p14/MP1/MEK/ERK signaling module. Finally, the proliferation defect was confirmed in a chemically induced liver regeneration model in p14 liver knock-out mice.
Comprehensive proteomic and transcriptomic characterization of hepatic expression signatures affected in p14 liver conditional knockout mice.
Specimen part
View SamplesBackground and Aims: Although the zinc finger transcription factor GATA4 has been implicated in regulating jejunal gene expression, the contribution of GATA4 in controlling jejunal physiology has not been addressed. Methods: We generated mice in which the Gata4 gene was specifically deleted in the small intestinal epithelium. Measurements of plasma cholesterol and phospholipids, intestinal absorption of dietary fat and cholesterol, and gene expression were performed on these animals. Results: Mice lacking GATA4 in the intestine displayed a dramatic block in their ability to absorb cholesterol and dietary fat. Comparison of the global gene expression profiles of control jejunum, control ileum, and GATA4 null jejunum by gene array analysis demonstrated that GATA4 null jejunum lost expression of 53% of the jejunal-specific gene set and gained expression of 47% of the set of genes unique to the ileum. These alterations in gene expression included a decrease in mRNAs encoding lipid and cholesterol transporters as well as an increase in mRNAs encoding proteins involved in bile acid absorption. Conclusion: Our data demonstrate that GATA4 is essential for jejunal function including fat and cholesterol absorption and confirm that GATA4 plays a pivotal role in determining jejunal versus ileal identity.
GATA4 is essential for jejunal function in mice.
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View SamplesRenal excretion of water and major electrolytes exhibits a significant circadian rhythm. This functional periodicity is believed to result, at least in part, from circadian changes in secretion/reabsorption capacities of the distal nephron and collecting ducts. Here, we studied the molecular mechanisms underlying circadian rhythms in the distal nephron segments, i.e. distal convoluted tubule (DCT) and connecting tubule (CNT) and, the cortical collecting duct (CCD). Temporal expression analysis performed on microdissected mouse DCT/CNT or CCD revealed a marked circadian rhythmicity in the expression of a large number of genes crucially involved in various homeostatic functions of the kidney. This analysis also revealed that both DCT/CNT and CCD possess an intrinsic circadian timing system characterized by robust oscillations in the expression of circadian core clock genes (clock, bma11, npas2, per, cry, nr1d1) and clock-controlled Par bZip transcriptional factors dbp, hlf and tef. The clock knockout mice or mice devoid of dbp/hlf/tef (triple knockout) exhibit significant changes in renal expression of several key regulators of water or sodium balance (vasopressin V2 receptor, aquaporin-2, aquaporin-4, alphaENaC). Functionally, the loss of clock leads to a complex phenotype characterized by partial diabetes insipidus, dysregulation of sodium excretion rhythms and a significant decrease in blood pressure. Collectively, this study uncovers a major role of molecular clock in renal function.
Molecular clock is involved in predictive circadian adjustment of renal function.
Sex, Specimen part
View SamplesQuaking are RNA binding proteins, which are known to regulate the expression of different genes at the post-transcriptional level. Genetic interference with quaking a (qkia) and quaking c (qkic) leads to major myofibril defects during zebrafish development, without affecting early muscle differentiation. In order to understand how qkia and qkic jointly regulate myofibril formation, we performed a comparative analysis of the transcriptome of qkia/qkic (qkia mutant injected with qkic morpholino) versus control embryos. We show that Quaking activity is required for accumulation of the muscle-specific tropomyosin 3 transcript, tpm3.1. Whereas interference with tmp3.1 function disrupts myofibril formation, reintroducing tpm3.1 transcripts into embryos with reduced Quaking activity can restore structured myofibrils. Thus, we identify tropomyosin as an essential component in the process of myofibril formation and as a relay downstream of the regulator proteins Quaking. Overall design: Transcriptome of control versus qkia/qkic embryos at 24-26hpf. Biological triplicate were prepared for both condition (3x2 samples).
Quaking RNA-Binding Proteins Control Early Myofibril Formation by Modulating Tropomyosin.
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View SamplesGenetically targeted mice with deficiency for the A2BAR show increased susceptibility to acute myocardial ischemia and are not protected by IP, a powerful strategy for cardioprotection, where short and repeated episodes of ischemia and reperfusion prior to myocardial infarction result in attenuation of infarct size.
Adora2b-elicited Per2 stabilization promotes a HIF-dependent metabolic switch crucial for myocardial adaptation to ischemia.
Sex, Age
View SamplesIn this study, we performed the gene expression analysis of the Normal, Diabetic and AAT treated NOD mice to elucidate the transcriptional changes induced by AAT. This will assist in identifying the biological processes / pathways involved in curative mechanism of AAT.
Curative and beta cell regenerative effects of alpha1-antitrypsin treatment in autoimmune diabetic NOD mice.
No sample metadata fields
View SamplesThe different stages of the optic fissure can be clearly visualized by making sagittal sections through the mouse eye during early development which represent the optic fissure at open (E10.5), closing (E11.5) and fused (E12.5) states. Laser capture microdissection (LCM) was employed to dissect tissue from the margins of the optic fissure consisting of the outer (presumptive RPE) and inner (presumptive neurosensory retina) layers of the retina.
Expression profiling during ocular development identifies 2 Nlz genes with a critical role in optic fissure closure.
No sample metadata fields
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