title: Mouse Ripply2 is downstream of Wnt3a and is dynamically expressed during somitogenesis.
abstract: Somites are blocks of mesoderm that form when segment boundaries are periodically generated in the anterior presomitic mesoderm (PSM). Periodicity is thought to be driven by an oscillating Notch-centered segmentation clock, whereas boundaries are spatially positioned by the secreted signaling molecules Wnt3a and Fgf8. We identified the putative transcriptional corepressor Ripply2 as a differentially expressed gene in wild-type and Wnt3a(-/-) embryos. Here, we show that Ripply2 is expressed in the anterior PSM and that it indeed lies downstream of Wnt3a. Dynamic Ripply2 expression in prospective somites S0 and S-I overlaps with the rostral expression of cycling genes in the Notch pathway, suggesting that Ripply2 may be controlled by the segmentation clock. Continued expression of Ripply2 in embryos lacking Hes7, a molecular oscillator in the Notch clock, indicates that Hes7 is not a major regulator of Ripply2. Our data are consistent with Ripply2 functioning as a segment boundary determination gene during mammalian embryogenesis. Developmental
authors.affiliation: Cancer and Developmental Biology Laboratory, Center for Cancer Research, NCI-Frederick, NIH, Frederick, Maryland 21702, USA.
authors.forename: Kristin K
authors.initials: KK
authors.lastname: Biris
authors.forename: William C
authors.initials: WC
authors.lastname: Dunty
authors.forename: Terry P
authors.initials: TP
authors.lastname: Yamaguchi
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D047108:Embryonic Development; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D016695:Glycosyltransferases / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism; D017403:In Situ Hybridization; D008648:Mesoderm / Q000196:embryology* / Q000378:metabolism; D051379:Mice; D051880:Receptors, Notch / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism*; D019170:Somites / Q000196:embryology* / Q000378:metabolism; D051153:Wnt Proteins / Q000378:metabolism*; D060508:Wnt3 Protein; D060509:Wnt3A Protein
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D016326:Extracellular Matrix Proteins; D016695:Glycosyltransferases; D018398:Homeodomain Proteins; D051880:Receptors, Notch; D012097:Repressor Proteins; D051153:Wnt Proteins; D060508:Wnt3 Protein; D060509:Wnt3A Protein; C430525:Hes7 protein, mouse; C107407:Mesp2 protein, mouse; C520509:Ripply2 protein, mouse; C093234:Tcf15 protein, mouse; C108545:Uncx4.1 protein, mouse; C555511:Wnt3a protein, mouse; C498392:Lfng protein, mouse