Direct and indirect roles of CNS dorsal midline cells in choroid plexus epithelia formation.
Choroid plexus (CP) produces the cerebrospinal fluid (CSF) of the central nervous system (CNS), but little is known about the mechanisms underlying development of this important tissue. CP forms in the hindbrain (4th ventricle), diencephalon (3rd ventricle) and dorsomedial telencephalon bilaterally (lateral ventricles). All of these sites lie at or near the embryonic dorsal midline (DM), which acts as a CNS patterning center. We therefore examined DM-CP relationships using normal and Gdf7 (Bmp12) transgenic embryos to fate map or ablate DM cells. These studies revealed a Gdf7 fate map that includes most CP epithelial (CPe) cells of the hindbrain and diencephalon. In the telencephalon, Gdf7 cell lineages were found in the small anterior domain of telencephalic CPe (tCPe), but its large posterior domain was devoid of these lineages. Anterior and posterior tCPe domains, which arise within a contiguous field separate from diencephalic CPe, also exhibited different patterns of apoptosis. Despite lacking Gdf7 cell lineages, the posterior tCPe domain failed to form after ablating Gdf7-expressing DM cells at neural tube stages. The tCPe loss was associated with abrogation of high-level bone morphogenetic protein (Bmp) signaling, which is known to be required for tCPe induction. Taken together, these studies demonstrate intimate DM-CPe relationships throughout the CNS and highlight two distinct tCPe domains, including a posterior domain whose genesis depends on DM cells in a non-cell-autonomous fashion.
Department of Pathology, University of California, Irvine, D440 Medical Sciences I, Irvine, CA 92697-4800, USA.
D Spencer
DS
Currle
Xun
X
Cheng
Ching-Mei
CM
Hsu
Edwin S
ES
Monuki
D000818:Animals; D019521:Body Patterning; D019485:Bone Morphogenetic Proteins / Q000172:deficiency / Q000235:genetics*; D002831:Choroid Plexus / Q000166:cytology / Q000196:embryology*; D047108:Embryonic Development; D004847:Epithelial Cells / Q000166:cytology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D055412:Growth Differentiation Factors; D008636:Mesencephalon / Q000196:embryology; D051379:Mice; D018345:Mice, Knockout; D009420:Nervous System / Q000196:embryology; D011247:Pregnancy; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000235:genetics
D019485:Bone Morphogenetic Proteins; C499471:Gdf7 protein, mouse; D055412:Growth Differentiation Factors; D016212:Transforming Growth Factor beta; C086559:growth differentiation factor 7