title: Nonautonomous Roles of MAB-5/Hox and the Secreted Basement Membrane Molecule SPON-1/F-Spondin in Caenorhabditis elegans Neuronal Migration.
abstract: Nervous system development and circuit formation requires neurons to migrate from their birthplaces to specific destinations.Migrating neurons detect extracellular cues that provide guidance information. In Caenorhabditis elegans, the Q right (QR) and Q left (QL) neuroblast descendants migrate long distances in opposite directions. The Hox gene lin-39 cell autonomously promotes anterior QR descendant migration, and mab-5/Hox cell autonomously promotes posterior QL descendant migration. Here we describe a nonautonomous role of mab-5 in regulating both QR and QL descendant migrations, a role masked by redundancy with lin-39 A third Hox gene, egl-5/Abdominal-B, also likely nonautonomously regulates Q descendant migrations. In the lin-39 mab-5 egl-5 triple mutant, little if any QR and QL descendant migration occurs. In addition to well-described roles of lin-39 and mab-5 in the Q descendants, our results suggest that lin-39, mab-5, and egl-5 might also pattern the posterior region of the animal for Q descendant migration. Previous studies showed that the spon-1 gene might be a target of MAB-5 in Q descendant migration. spon-1 encodes a secreted basement membrane molecule similar to vertebrate F-spondin. Here we show that spon-1 acts nonautonomously to control Q descendant migration, and might function as a permissive rather than instructive signal for cell migration. We find that increased levels of MAB-5 in body wall muscle (BWM) can drive the spon-1 promoter adjacent to the Q cells, and loss of spon-1 suppresses mab-5 gain of function. Thus, MAB-5 might nonautonomously control Q descendant migrations by patterning the posterior region of the animal to which Q cells respond. spon-1 expression from BWMs might be part of the posterior patterning necessary for directed Q descendant migration.
authors.affiliation: Department of Molecular Biosciences, Programs in Genetics and Molecular, Cellular, and Developmental Biology, University of Kansas, Lawrence, Kansas 66045.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Josephson
authors.affiliation: Department of Molecular Biosciences, Programs in Genetics and Molecular, Cellular, and Developmental Biology, University of Kansas, Lawrence, Kansas 66045.
authors.forename: Adam M
authors.initials: AM
authors.lastname: Miltner
authors.affiliation: Department of Molecular Biosciences, Programs in Genetics and Molecular, Cellular, and Developmental Biology, University of Kansas, Lawrence, Kansas 66045 erikl@ku.edu.
authors.forename: Erik A
authors.identifier: 0000-0001-6819-4815
authors.initials: EA
authors.lastname: Lundquist
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000235:genetics / Q000254:growth & development; D029742:Caenorhabditis elegans Proteins / Q000235:genetics*; D002465:Cell Movement / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D018398:Homeodomain Proteins / Q000235:genetics*; D009132:Muscles / Q000294:innervation / Q000378:metabolism; D058953:Neural Stem Cells / Q000378:metabolism; D055495:Neurogenesis / Q000235:genetics*; D009474:Neurons / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D029742:Caenorhabditis elegans Proteins; C477318:Egl-5 protein, C elegans; D016326:Extracellular Matrix Proteins; D018398:Homeodomain Proteins; C081538:Mab-5 protein, C elegans; D014157:Transcription Factors; C108673:lin-39 protein, C elegans; C533066:spon-1 protein, C elegans
keywords: F-spondin; Hox; cell migration; egl-5; mab-5