Signaling Pathways and Axis Formation in the Lower Metazoa

• Published in: Current Topics in Developmental Biology Vol. 97; pp. 137 - 177
• Main Authors: Holstein, Thomas W., Watanabe, Hiroshi, Özbek, Suat
• Format: Book Chapter Journal Article
• Language: English
• Published: United States Elsevier Science & Technology 2011
• Subjects: Animals; beta Catenin - genetics; beta Catenin - metabolism; Biological Evolution; Body axis; Body Patterning - genetics; Bone Morphogenetic Proteins - genetics; Bone Morphogenetic Proteins - metabolism; Gene Expression Regulation, Developmental; Genes, Homeobox - genetics; Invertebrates - classification; Invertebrates - genetics; Metazoan origin; Molecular Sequence Data; Nodal Protein - genetics; Nodal Protein - metabolism; Patterning; Phylogeny; Receptors, Transforming Growth Factor beta - genetics; Receptors, Transforming Growth Factor beta - metabolism; Signaling pathways; Smad Proteins - genetics; Smad Proteins - metabolism; Ur-bilaterian; Wnt Proteins - genetics; Wnt Proteins - metabolism; Wnt Signaling Pathway - genetics; Signaling pathways; Ur-bilaterian; Patterning; Metazoan origin; Body axis
• ISBN: 9780123859754; 0123859751
• ISSN: 0070-2153; 1557-8933
• DOI: 10.1016/B978-0-12-385975-4.00012-7

The determination of the body axis in the last common ancestor of bilaterian animals is still a matter of debate. While Hox genes pattern the formation of the primary, anteroposterior body axis in bilaterians, there is growing evidence from lower metazoans that the Wnt/β-catenin pathway acts as the primordial signaling system in this process. This review summarizes molecular data from recent genomic analyses of basal model organisms with a focus on the evolution of signaling pathways involved in the establishment of the primary and successive body axes during early metazoan evolution.