Project description:The transcription factor Egr3 has been shown to have a cell autonomous role in sympathetic nervous system (SNS) development. We utilized microarray analysis to identify potential downstream target genes deregulated with loss of Egr3. Both conditions were in the null Bax background to prevent apoptosis and therefore mitigate identification of apoptosis related genes. Our analysis identified genes involved in biological processes that were expected such as SNS development and axonogenesis as well as those that were unexpected such as dendritogenesis and axon guidance. This led us to investigate whether Egr3 is important in these unexpected biological processes within sympathetic neurons. Total RNA was obtained from superior cervical ganglion (SCG) dissected from P0 mice with the genotype of Egr3+/+; Bax-/- or Egr3-/-; Bax-/-. Each genotype had 3 samples each.
Project description:The transcription factor Egr3 has been shown to have a cell autonomous role in sympathetic nervous system (SNS) development. We utilized microarray analysis to identify potential downstream target genes deregulated with loss of Egr3. Both conditions were in the null Bax background to prevent apoptosis and therefore mitigate identification of apoptosis related genes. Our analysis identified genes involved in biological processes that were expected such as SNS development and axonogenesis as well as those that were unexpected such as dendritogenesis and axon guidance. This led us to investigate whether Egr3 is important in these unexpected biological processes within sympathetic neurons.
Project description:We performed scRNA-seq analysis on sympathetic ganglia, including the superior cervical ganglion (SCG), stellate ganglion (SG), and coeliac–superior mesenteric ganglion (CG-SMG). Comparative analysis of the transcriptomic profiling revealed molecularly distinct cell subtypes. We then performed scRNA-seq analysis in SCG and CG-SMG under control and stressed conditions (cold and microbiota-depletion). These analyses show that sympathetic ganglia undergo dynamic remodeling under stress, with distinct stressors driving ganglion-specific plasticity directly coupled to altered neuronal function.
Project description:The superior cervical ganglion (SCG) innervates multiple effector organs within cranial tissues and elicits responses including pupil dilation, piloerection, vasoconstriction and inhibition of salivation. Coordinated activation of these targets is associated with the display of different emotions; however, the underlying circuit organization and cellular heterogeneity of SCG neurons remain unclear. Here, we combined neuronal tracing with single-cell and spatial transcriptomics to characterize the SCG circuitry and heterogeneity. We found that each SCG neuron innervates a single effector organ. SCG subtypes defined by their projection (P) targets form two major compartments within the ganglia, but individual P-types were intermingled. Mature SCG transcriptomic types (T) emerge postnatally and exhibit rostra-caudal biases. While some T-types were enriched in SCG populations with specific axon projections, they did not show a strict one-to-one correspondence with P-types. These results suggest that individual sympathetic cranial effectors mediating facial emotions are controlled combinatorially by multiple transcriptomic SCG types.
Project description:The superior cervical ganglion (SCG) innervates multiple effector organs within cranial tissues and elicits responses including pupil dilation, piloerection, vasoconstriction and inhibition of salivation. Coordinated activation of these targets is associated with the display of different emotions; however, the underlying circuit organization and cellular heterogeneity of SCG neurons remain unclear. Here, we combined neuronal tracing with single-cell and spatial transcriptomics to characterize the SCG circuitry and heterogeneity. We found that each SCG neuron innervates a single effector organ. SCG subtypes defined by their projection (P) targets form two major compartments within the ganglia, but individual P-types were intermingled. Mature SCG transcriptomic types (T) emerge postnatally and exhibit rostra-caudal biases. While some T-types were enriched in SCG populations with specific axon projections, they did not show a strict one-to-one correspondence with P-types. These results suggest that individual sympathetic cranial effectors mediating facial emotions are controlled combinatorially by multiple transcriptomic SCG types.
Project description:To uncover Meis1 functions during the embryonic development of sympathetic neurons, we perfomed a ChIP-seq analysis from mouse E16 embryonic superior cervical ganglia (SCG) using an antibody against Meis1. We identified 309 potential target genes with a particular enrichment in genes involved in vesicles formation, function and trafficking, leading to the hypothesis that Meis1 participate in late sympathetic neurons differentiation by coordinating target-field innervation, synaptogenesis and survival through the transcriptional control of the machinery necessary for endocytosis and exocytosis. We further confirmed that the expression of some of these genes was lost and/or modified in E16 SCGs of a HtPACRE/Meis1LoxP/LoxP mouse strain compared to wild type littermates. We additionaly confirmed that endocytosis and synaptogenesis is impaired in those mutants.
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:Disruption of the physiologic sleep-wake cycle and low melatonin levels frequently accompany cardiac disease, yet the underlying mechanism has remained enigmatic. Immunostaining of sympathetic axons in optically cleared pineal glands from humans and mice with cardiac disease revealed their substantial denervation compared to controls. Spatial, single-cell, nuclear, and bulk RNA sequencing traced this defect back to the superior cervical ganglia (SCG), which responded to cardiac disease with accumulation of inflammatory macrophages, fibrosis, and the selective loss of pineal gland-innervating neurons. Depletion of macrophages in the SCG prevented disease-associated denervation of the pineal gland and restored physiological melatonin secretion. Our data identify the mechanism underlying the disturbance of diurnal rhythmicity in cardiac disease and suggest means for therapeutic intervention.