Project description:Background: The molecular identification of neural progenitor cell populations that connect to establish the sympathetic nervous system (SNS) remains unclear. This is due to technical limitations in the acquisition and spatial mapping of molecular information to tissue architecture. Results: To address this, we applied Slide-seq spatial transcriptomics to intact fresh frozen chick trunk tissue transversely cryo-sectioned at the developmental stage prior to SNS formation. In parallel, we performed age- and location-matched single cell (sc) RNA-seq and 10x Genomics Visium to inform our analysis. Downstream bioinformatic analyses led to the unique molecular identification of neural progenitor cells within the peripheral sympathetic ganglia (SG) and spinal cord preganglionic neurons (PGNs). We then successfully applied the HiPlex RNAscope fluorescence in situ hybridization and multispectral confocal microscopy to visualize 12 gene targets in stage-, age- and location-matched chick trunk tissue sections. Conclusions: Together, these data demonstrate a robust strategy to acquire and integrate single cell and spatial transcriptomic information, resulting in improved resolution of molecular heterogeneities in complex neural tissue architectures. Successful application of this strategy to the developing SNS provides a roadmap for functional studies of neural connectivity and platform to address complex questions in neural development and regeneration.
Project description:Background: The molecular identification of neural progenitor cell populations that connect to establish the sympathetic nervous system (SNS) remains unclear. This is due to technical limitations in the acquisition and spatial mapping of molecular information to tissue architecture. Results: To address this, we applied Slide-seq spatial transcriptomics to intact fresh frozen chick trunk tissue transversely cryo-sectioned at the developmental stage prior to SNS formation. In parallel, we performed age- and location-matched single cell (sc) RNA-seq and 10x Genomics Visium to inform our analysis. Downstream bioinformatic analyses led to the unique molecular identification of neural progenitor cells within the peripheral sympathetic ganglia (SG) and spinal cord preganglionic neurons (PGNs). We then successfully applied the HiPlex RNAscope fluorescence in situ hybridization and multispectral confocal microscopy to visualize 12 gene targets in stage-, age- and location-matched chick trunk tissue sections. Conclusions: Together, these data demonstrate a robust strategy to acquire and integrate single cell and spatial transcriptomic information, resulting in improved resolution of molecular heterogeneities in complex neural tissue architectures. Successful application of this strategy to the developing SNS provides a roadmap for functional studies of neural connectivity and platform to address complex questions in neural development and regeneration.
Project description:Background: The molecular identification of neural progenitor cell populations that connect to establish the sympathetic nervous system (SNS) remains unclear. This is due to technical limitations in the acquisition and spatial mapping of molecular information to tissue architecture. Results: To address this, we applied Slide-seq spatial transcriptomics to intact fresh frozen chick trunk tissue transversely cryo-sectioned at the developmental stage prior to SNS formation. In parallel, we performed age- and location-matched single cell (sc) RNA-seq and 10x Genomics Visium to inform our analysis. Downstream bioinformatic analyses led to the unique molecular identification of neural progenitor cells within the peripheral sympathetic ganglia (SG) and spinal cord preganglionic neurons (PGNs). We then successfully applied the HiPlex RNAscope fluorescence in situ hybridization and multispectral confocal microscopy to visualize 12 gene targets in stage-, age- and location-matched chick trunk tissue sections. Conclusions: Together, these data demonstrate a robust strategy to acquire and integrate single cell and spatial transcriptomic information, resulting in improved resolution of molecular heterogeneities in complex neural tissue architectures. Successful application of this strategy to the developing SNS provides a roadmap for functional studies of neural connectivity and platform to address complex questions in neural development and regeneration.
Project description:Cell-Type Profiling of the Sympathetic Nervous System Using Spatial Transcriptomics and Spatial Mapping of mRNA [Spatial Transcriptomics]
Project description:Neuroblastoma is an embryonal neoplasm that remains of dramatic prognosis in its aggressive forms. Activating mutations of the ALK tyrosine kinase receptor have been identified in sporadic and familial cases of this cancer. We generated knock-in mice carrying an F1178L Alk mutation corresponding to the ALK F1174L mutation observed in neuroblastoma patients We used microarrays to detail the global programme of gene expression underlying the impact of ALK F1178L mutation on sympathetic nervous system ganglia We selected sympathetic nervous system ganglia (superior cervical and stellate ganglia) for RNA extraction and hybridization on Affymetrix microarrays. We profiled a total number of 12 Po (4 Wt; 4 Hz; 4 Ho) and 5 P18 (3 Wt; 2 Hz)
Project description:The sympathetic nervous system controls a wide spectrum of bodily functions including operation of vessels, cardiac rhythm, and the “flight or fight response”. Sympathetic neurons, which are neural crest-derived, develop in coordination with presynaptic motor nerves extending from the central nervous system (CNS). By using nerve-selective genetic ablations, we revealed that sympathetic ganglia development depends on CNS-derived motor innervation. In the absence of preganglionic motor nerves, trunk sympathetic chain ganglia were fragmented and smaller in size, while cervical ganglia were severely misshapen. Sympathetic neurons were misplaced along sensory fibers and projected towards abnormal paths, in some cases invading the sensory dorsal root ganglia. The misplaced progenitors of sympathoblasts corresponded to the nerve-associated, neural crest-derived Schwann cell precursors (SCPs). Notably, we found that SCPs activate the autonomic marker PHOX2B while migrating along motor nerves towards the region of the dorsal aorta in wildtype embryos, suggesting that SCP differentiate into sympathetic neurons while still nerve-associated in motor-ablated embryos. Ligand-receptor prediction from single cell transcriptomic data coupled with functional studies identified Semaphorin 3A/3F as candidate motor nerve-derived signals influencing neural crest migration along axons. Thus, motor nerves control the placement of sympathoblasts and their subsequent axonal navigation during critical periods of sympathetic chain development.
Project description:Neuroblastoma is an embryonal neoplasm that remains of dramatic prognosis in its aggressive forms. Activating mutations of the ALK tyrosine kinase receptor have been identified in sporadic and familial cases of this cancer. We generated knock-in mice carrying an F1178L Alk mutation corresponding to the ALK F1174L mutation observed in neuroblastoma patients We used microarrays to detail the global programme of gene expression underlying the impact of ALK F1178L mutation on sympathetic nervous system ganglia