title: The roof plate regulates cerebellar cell-type specification and proliferation.
abstract: During embryogenesis, the isthmic organizer, a well-described signaling center at the junction of the mid-hindbrain, establishes the cerebellar territory along the anterior/posterior axis of the neural tube. Mechanisms specifying distinct populations within the early cerebellar anlage are less defined. Using a newly developed gene expression map of the early cerebellar anlage, we demonstrate that secreted signals from the rhombomere 1 roof plate are both necessary and sufficient for specification of the adjacent cerebellar rhombic lip and its derivative fates. Surprisingly, we show that the roof plate is not absolutely required for initial specification of more distal cerebellar cell fates, but rather regulates progenitor proliferation and cell position within the cerebellar anlage. Thus, in addition to the isthmus, the roof plate represents an important signaling center controlling multiple aspects of cerebellar patterning.
authors.affiliation: Department of Human Genetics, University of Chicago, 920 E. 58th Street, CLSC 319 Chicago, IL 60637, USA.
authors.forename: Victor V
authors.initials: VV
authors.lastname: Chizhikov
authors.forename: Anne G
authors.initials: AG
authors.lastname: Lindgren
authors.forename: D Spencer
authors.initials: DS
authors.lastname: Currle
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Rose
authors.forename: Edwin S
authors.initials: ES
authors.lastname: Monuki
authors.forename: Kathleen J
authors.initials: KJ
authors.lastname: Millen
mesh_terms: D000818:Animals; D002455:Cell Division; D002468:Cell Physiological Phenomena; D002531:Cerebellum / Q000002:abnormalities / Q000196:embryology*; D000013:Congenital Abnormalities / Q000196:embryology / Q000473:pathology; D047108:Embryonic Development; D051379:Mice; D008817:Mice, Mutant Strains; D009436:Neural Tube Defects / Q000473:pathology; D013116:Spinal Cord / Q000196:embryology / Q000254:growth & development