Analysis of Netrin 1 receptors during inner ear development.
Netrin 1 plays key roles in axon guidance and neuronal migration during central nervous system (CNS) development. Outside the CNS, Netrin 1 has been shown to be involved in epithelial morphogenesis of various organs. We have shown that Netrin 1 is essential for inner ear semicircular duct formation, but the involvement of Netrin 1 receptors in this process has remained unknown. Netrin 1 receptors include members of the Deleted in colorectal cancer (Dcc), Unc5-homologue and integrin families. Here we have analysed the expression of these receptor genes during inner ear development and verified the inner ear phenotypes of several receptor mutant mice. Special interest was directed to receptors that could cooperate with Netrin 1 during semicircular duct formation. We show that Neogenin (Neo1), Unc5c as well as integrin b1 (Itgb1) are expressed in periotic mesenchyme, while Dcc, Unc5b, Unc5c, Itga3, Itga6 and Itgb1 are expressed in different parts of the otic epithelium. In spite of the broad and strong expression of several receptors in ear region, none of the analysed receptor mutant embryos showed any defects in inner ear development.
Matilainen
Tanja
T
Developmental Biology Program, Institute of Biotechnology, University of Helsinki, Finland, and Department of Medicine, The Children's Hospital, Boston, MA, USA.
Haugas
Maarja
M
Kreidberg
Jordan A
JA
Salminen
Marjo
M
D000818:Animals; D000075389:DCC Receptor; D007758:Ear, Inner / Q000196:embryology* / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D016023:Integrins / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D009414:Nerve Growth Factors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D000075386:Netrin Receptors; D000075388:Netrin-1; D021122:Protein Subunits / Q000235:genetics; D011956:Receptors, Cell Surface / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D025521:Tumor Suppressor Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism
D000075389:DCC Receptor; C501910:Dcc protein, mouse; D016023:Integrins; D009414:Nerve Growth Factors; D000075386:Netrin Receptors; C000617353:Ntn1 protein, mouse; D021122:Protein Subunits; D011956:Receptors, Cell Surface; D025521:Tumor Suppressor Proteins; D000075388:Netrin-1