title: Secreted Wnt "inhibitors" are not just inhibitors: regulation of extracellular Wnt by secreted Frizzled-related proteins.
abstract: Gradient formation and signaling ranges of secreted proteins are crucial problems to understand how morphogens work for positional information and patterning in animal development. Yet, extracellular behaviors of secreted signaling molecules remain unexplored compared to their downstream pathways inside the cell. Recent advances in bioimaging make it possible to directly visualize morphogen molecules, and this simple strategy has, at least partly, succeeded in uncovering molecular behaviors of morphogens, such as Wnt (wingless-type MMTV integration site family member) and BMP (bone morphogenetic protein) as well as secreted Wnt binding proteins, sFRPs (secreted Frizzled-related proteins), in embryonic tissues. Here, we review the regulation of Wnt signaling by sFRPs, focusing on extracellular regulation of Wnt ligands in comparison with other morphogens. We also discuss evolutionary aspects with comprehensive syntenic and phylogenetic information about vertebrate sfrp genes. We newly annotated several sfrp genes including sfrp2-like 1 (sfrp2l1) in frogs and fishes and crescent in mammals.
authors: Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors: Yusuke
authors: Y
authors: Mii
authors: Masanori
authors: M
authors: Taira
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005110:Extracellular Space / Q000378:metabolism; D051157:Frizzled Receptors / Q000378:metabolism / Q000502:physiology; D006023:Glycoproteins / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D009024:Morphogenesis / Q000235:genetics / Q000502:physiology; D010802:Phylogeny; D051153:Wnt Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D000099274:Frizzled-Related Proteins
chemical_list: D002352:Carrier Proteins; D051157:Frizzled Receptors; D006023:Glycoproteins; D047908:Intracellular Signaling Peptides and Proteins; D051153:Wnt Proteins; D000099274:Frizzled-Related Proteins