Project description:The choroid plexus (ChP) produces cerebrospinal fluid and forms an essential brain barrier. ChP tissues form in each brain ventricle, each one adopting a distinct shape, but remarkably little is known about the mechanisms underlying ChP development. Here, we show that epithelial WNT5A is crucial for determining fourth ventricle (4V) ChP morphogenesis and size in mouse. Systemic Wnt5a knockout, or forced Wnt5a overexpression beginning at embryonic day 10.5, profoundly reduced ChP size and development. However, Wnt5a expression was enriched in Foxj1-positive epithelial cells of 4V ChP plexus, and its conditional deletion in these cells affected the branched, villous morphology of the 4V ChP. We found that WNT5A was enriched in epithelial cells localized to the distal tips of 4V ChP villi, where WNT5A acted locally to activate non-canonical WNT signaling via ROR1 and ROR2 receptors. During 4V ChP development, MEIS1 bound to the proximal Wnt5a promoter, and gain- and loss-of-function approaches demonstrated that MEIS1 regulated Wnt5a expression. Collectively, our findings demonstrate a dual function of WNT5A in ChP development and identify MEIS transcription factors as upstream regulators of Wnt5a in the 4V ChP epithelium.
Project description:We used microarrays to reveal the global expression profiles of young and old whole lateral ventricle choroid plexus tissue. RNA was isolated from whole lateral ventricle choroid plexus tissue followed by RNA amplification and hybridization on Affymetrix microarrays. Each sample contains both lateral ventricle choroid plexi from one male CD1 mouse. A total of six samples (three biological replicates from 2 different ages) were analyzed.
Project description:Atoh1-Cre; Myc/Myc mice developed choroid plexus papilloma and Atoh1-Cre; Myc/Myc; p53fl/fl mice developed choroid plexus carcinoma. By studying the gene expression profiles of normal choroid plexus, choroid plexus papilloma and choroid plexus carcinoma in mice, we aim to gain a better understanding of the biology of choroid plexus tumors
Project description:A sheet of choroid plexus epithelial cells extends into each cerebral ventricle and secretes signaling factors into the cerebrospinal fluid (CSF). To evaluate whether differences in the CSF proteome across ventricles arise, in part, from regional differences in choroid plexus gene expression, we defined the transcriptome of lateral ventricle (telencephalic) vs. fourth ventricle (hindbrain) choroid plexus. We find that positional identities of mouse, macaque, and human choroid plexi derive from gene expression domains that parallel their axial tissues of origin. We then show that molecular heterogeneity between telencephalic and hindbrain choroid plexi contributes to region-specific, age-dependent protein secretion in vitro. Transcriptome analysis of FACS-purified choroid plexus epithelial cells also predicts their cell type-specific secretome. Spatial domains with distinct protein expression profiles were observed within each choroid plexus. We propose that regional differences between choroid plexi contribute to dynamic signaling gradients across the mammalian cerebroventricular system.
Project description:We report the transcription profiling of choroid plexus at 4 developmental stages, E12,5, P0, P14 and 6 month. We also compared wildtype and Foxj1-/- choroid plexus transcriptome at P0.
Project description:The choroid plexus (ChP) in each brain ventricle produces cerebrospinal fluid (CSF) and forms the blood-CSF barrier. We apply single cell and single nuclei sequencing to identify region and age specific shifts in gene expression of the constituent cell types of the choroid plexus. First, we sequenced whole cells (15,620) from each ventricle (lateral, third and fourth) of the embryonic mouse brain (Embryonic day (E) 16.5). Our analyses and validation of gene (smFISH) and protein (immunohistochemistry) expression combined with spatial mapping (confocal imaging) revealed the identity and location of major cell types, subtypes, proliferating cells, progenitor populations and regionalized gene expression, across each ventricle in the developing brain. Next, to track age-dependent shifts in the choroid plexus properties, we performed single nuclei sequencing (83,040) across each ventricle of the embryonic (E16.5), adult (4 months) and aging (20 months) mouse brain. Epithelial and mesenchymal cells showed regionalized gene expression patterns by ventricle, starting at embryonic stages and persisting with age. Dramatic transcriptional shifts were found with maturation (embryonic to adult) and a smaller shift within each aged cell type. With aging, epithelial cells upregulated host defense programs and resident macrophages enhanced expression of IL-1b signaling genes. Our atlas revealed ChP brain barrier cellular diversity, architecture and signaling across ventricles during development, maturation and aging.
Project description:The choroid plexus produces cerebrospinal fluid (CSF) by transport of electrolytes and water from the vasculature to the brain ventricles. The choroid plexus plays additional roles in brain development and homeostasis by secreting neurotrophic molecules, and by serving as a CSF-blood barrier and immune interface. Prior studies have identified transporters on the epithelial cells that transport water and ions into the ventricles and tight junctions involved in the CSF-blood barrier. Yet, how the choroid plexus epithelial cells maintain the brain ventricle system and control brain physiology remain unresolved. To provide novel insights into the physiological roles of the choroid plexus, we use juvenile and adult zebrafish as model systems. Upon histological and transcriptomic analyses, we first identified that the zebrafish choroid plexus is highly conserved with the mammalian choroid plexus and that it expresses all transporters necessary for CSF secretion. Using novel genetic lines, we also identified that the choroid plexus secretes proteins into the CSF. Next, we generated a transgenic line allowing us to ablate specifically the epithelial cells in the choroid plexus. Using the ablation system, we identified a reduction of the ventricular sizes, but no alterations of the CSF-blood barrier. Altogether, our findings identified that the zebrafish choroid plexus is evolutionarily conserved and critical for maintaining the size and homeostasis of the brain ventricles.