The Nogo-C2/Nogo Receptor Complex Regulates the Morphogenesis of Zebrafish Lateral Line Primordium through Modulating the Expression of dkk1b, a Wnt Signal Inhibitor

The fish lateral line (LL) is a mechanosensory system closely related to the hearing system of higher vertebrates, and it is composed of several neuromasts located on the surface of the fish. These neuromasts can detect changes in external water flow, to assist fish in maintaining a stationary position in a stream. In the present study, we identified a novel function of Nogo/Nogo receptor signaling in the formation of zebrafish neuromasts. Nogo signaling in zebrafish, like that in mammals, involves three ligands and four receptors, as well as three co-receptors (TROY, p75, and LINGO-1). We first demonstrated that Nogo-C2, NgRH1a, p75, and TROY are able to form a Nogo-C2 complex, and that disintegration of this complex causes defective neuromast formation in zebrafish. Time-lapse recording of the CldnB::lynEGFP transgenic line revealed that functional obstruction of the Nogo-C2 complex causes disordered morphogenesis, and reduces rosette formation in the posterior LL (PLL) primordium during migration. Consistent with these findings, hair-cell progenitors were lost from the PLL primordium in p75, TROY, and Nogo-C2/NgRH1a morphants. Notably, the expression levels of pea3, a downstream marker of Fgf signaling, and dkk1b, a Wnt signaling inhibitor, were both decreased in p75, TROY, and Nogo-C2/NgRH1a morphants; moreover, dkk1b mRNA injection could rescue the defects in neuromast formation resulting from knockdown of p75 or TROY. We thus suggest that a novel Nogo-C2 complex, consisting of Nogo-C2, NgRH1a, p75, and TROY, regulates Fgf signaling and dkk1b expression, thereby ensuring stable organization of the PLL primordium.

[1]  A. Popper.  Hair cell heterogeneity and ultrasonic hearing: recent advances in understanding fish hearing. , 2000, Philosophical transactions of the Royal Society of London. Series B, Biological sciences.

[2]  N. Hukriede,et al.  The zebrafish dog-eared mutation disrupts eya1, a gene required for cell survival and differentiation in the inner ear and lateral line. , 2005, Developmental biology.

[3]  Qiling Xu,et al.  Pivotal role of hmx2 and hmx3 in zebrafish inner ear and lateral line development. , 2010, Developmental biology.

[4]  M. Matsuda,et al.  Atoh1a expression must be restricted by Notch signaling for effective morphogenesis of the posterior lateral line primordium in zebrafish , 2010, Development.

[5]  K. Garcia,et al.  A TNF Receptor Family Member, TROY, Is a Coreceptor with Nogo Receptor in Mediating the Inhibitory Activity of Myelin Inhibitors , 2005, Neuron.

[6]  T. Hirano,et al.  Zebrafish Dkk1 functions in forebrain specification and axial mesendoderm formation. , 2000, Developmental biology.

[7]  Nicolas Cubedo,et al.  Control of cell migration in the development of the posterior lateral line: antagonistic interactions between the chemokine receptors CXCR4 and CXCR7/RDC1 , 2007, BMC Developmental Biology.

[8]  W. K. Metcalfe.  Sensory neuron growth cones comigrate with posterior lateral line primordial cells in zebrafish , 1985, The Journal of comparative neurology.

[9]  Michael Klinger,et al.  A reticular rhapsody: phylogenic evolution and nomenclature of the RTN/Nogo gene family 1 , 2003, FASEB journal : official publication of the Federation of American Societies for Experimental Biology.

[10]  Zhan Yin,et al.  Role of Zebrafish Lbx2 in Embryonic Lateral Line Development , 2011, PloS one.

[11]  C. Kimmel,et al.  Stages of embryonic development of the zebrafish , 1995, Developmental dynamics : an official publication of the American Association of Anatomists.

[12]  Yusuke Nakamura,et al.  DKK1, a negative regulator of Wnt signaling, is a target of the β-catenin/TCF pathway , 2004, Oncogene.

[13]  A. Ghysen,et al.  Molecular basis of cell migration in the fish lateral line: Role of the chemokine receptor CXCR4 and of its ligand, SDF1 , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[14]  C. Albanese,et al.  The cyclin D1 gene is a target of the beta-catenin/LEF-1 pathway. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[15]  Zhigang He,et al.  Signaling mechanisms of the myelin inhibitors of axon regeneration , 2003, Current Opinion in Neurobiology.

[16]  T. Kudoh,et al.  Identification of Sef, a novel modulator of FGF signalling , 2002, Nature Cell Biology.

[17]  J. Relton,et al.  LINGO-1 is a component of the Nogo-66 receptor/p75 signaling complex , 2004, Nature Neuroscience.

[18]  C. Nüsslein-Volhard,et al.  Towing of sensory axons by their migrating target cells in vivo , 2004, Nature Neuroscience.

[19]  J. Y. Kuwada,et al.  Chemokine signaling regulates sensory cell migration in zebrafish. , 2004, Developmental biology.

[20]  D. Gilmour,et al.  Dynamic Fgf signaling couples morphogenesis and migration in the zebrafish lateral line primordium , 2008, Development.

[21]  D. Raible,et al.  Signaling Pathways Regulating Zebrafish Lateral Line Development , 2009, Current Biology.

[22]  C. Nüsslein-Volhard,et al.  Zebrafish pea3 and erm are general targets of FGF8 signaling , 2001, Current Biology.

[23]  J. I. Izpisúa Belmonte,et al.  Dickkopf1 is required for embryonic head induction and limb morphogenesis in the mouse. , 2001, Developmental cell.

[24]  Darren Gilmour,et al.  Chemokine signaling mediates self-organizing tissue migration in the zebrafish lateral line. , 2006, Developmental cell.

[25]  H. Lehrach,et al.  Zebrafish Dkk1, induced by the pre-MBT Wnt signaling, is secreted from the prechordal plate and patterns the anterior neural plate , 2000, Mechanisms of Development.

[26]  D. Raible,et al.  FGF-Dependent Mechanosensory Organ Patterning in Zebrafish , 2008, Science.

[27]  A. Ghysen,et al.  Cell proliferation in the developing lateral line system of zebrafish embryos , 2005, Developmental dynamics : an official publication of the American Association of Anatomists.

[28]  D. Raible,et al.  Lef1 is required for progenitor cell identity in the zebrafish lateral line primordium , 2011, Development.

[29]  Joshua S Kaminker,et al.  Death receptors DR6 and TROY regulate brain vascular development. , 2012, Developmental cell.

[30]  M. Halpern,et al.  Nogo–Nogo receptor signalling in PNS axon outgrowth and pathfinding , 2009, Molecular and Cellular Neuroscience.

[31]  A. Aman,et al.  Wnt/beta-catenin and Fgf signaling control collective cell migration by restricting chemokine receptor expression. , 2008, Developmental cell.

[32]  Dong Liu,et al.  The transmembrane inner ear (tmie) gene contributes to vestibular and lateral line development and function in the zebrafish (Danio rerio) , 2008, Developmental dynamics : an official publication of the American Association of Anatomists.

[33]  K. Kawakami,et al.  Identification and characterization of alternative promoters of zebrafish Rtn-4/Nogo genes in cultured cells and zebrafish embryos , 2010, Nucleic acids research.

[34]  M. Schwab,et al.  Analysis of the reticulon gene family demonstrates the absence of the neurite growth inhibitor Nogo-A in fish. , 2005, Molecular biology and evolution.

[35]  J. Pačes,et al.  Troy, a tumor necrosis factor receptor family member, interacts with lgr5 to inhibit wnt signaling in intestinal stem cells. , 2013, Gastroenterology.

[36]  Shui-Tsung Chen,et al.  Expression and characterization of a brain-specific protein kinase BSK146 from zebrafish. , 2006, Biochemical and biophysical research communications.

[37]  A. Ghysen,et al.  Somatotopy of the lateral line projection in larval zebrafish. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[38]  C. Niehrs,et al.  Dkk1 Regulates Ventral Midbrain Dopaminergic Differentiation and Morphogenesis , 2011, PloS one.

[39]  Quenten Schwarz,et al.  Lef1-dependent Wnt/β-catenin signalling drives the proliferative engine that maintains tissue homeostasis during lateral line development , 2011, Development.

[40]  M. Schwab.  Nogo and axon regeneration , 2004, Current Opinion in Neurobiology.

[41]  S. Millar,et al.  WNT signals are required for the initiation of hair follicle development. , 2002, Developmental cell.

[42]  John M. McCoy,et al.  TAJ/TROY, an Orphan TNF Receptor Family Member, Binds Nogo-66 Receptor 1 and Regulates Axonal Regeneration , 2005, Neuron.

[43]  J. Taylor,et al.  Identification of Nogo-66 receptor (NgR) and homologous genes in fish. , 2004, Molecular biology and evolution.

[44]  C. Petit,et al.  The zebrafish eya1 gene and its expression pattern during embryogenesis , 1999, Development Genes and Evolution.

[45]  D. Raible,et al.  Hedgehog signaling is directly required for the development of zebrafish dorsal root ganglia neurons , 2003, Development.

[46]  M. Westerfield,et al.  Caveolin-1 is required for lateral line neuromast and notochord development , 2007, Journal of Cell Science.

[47]  M. Hermann,et al.  Distinct expression patterns of dickkopf genes during late embryonic development of Danio rerio. , 2011, Gene expression patterns : GEP.

[48]  G. A. Wilkinson,et al.  Nogo-B receptor is essential for angiogenesis in zebrafish via Akt pathway. , 2010, Blood.

[49]  Choun-Ki Joo,et al.  Wnt/β-Catenin/Tcf Signaling Induces the Transcription of Axin2, a Negative Regulator of the Signaling Pathway , 2002, Molecular and Cellular Biology.

[50]  A. Ghysen,et al.  Development of the zebrafish lateral line , 2004, Current Opinion in Neurobiology.

[51]  C. Niehrs,et al.  Dickkopf-1 is a member of a new family of secreted proteins and functions in head induction , 1998, Nature.