title: The immunoglobulin superfamily protein SYG-1 determines the location of specific synapses in C. elegans.
abstract: During nervous system development, neurons form reproducible synapses onto specific targets. Here, we analyze the development of stereotyped synapses of the C. elegans HSNL neuron in vivo. Postsynaptic neurons and muscles were not required for accurate synaptic vesicle clustering in HSNL. Instead, vulval epithelial cells that contact HSNL act as synaptic guidepost cells that direct HSNL presynaptic vesicles to adjacent regions. The mutant syg-1(ky652) has defects in synapse formation that resemble those in animals that lack vulval epithelial cells: HSNL synaptic vesicles fail to accumulate at normal synaptic locations and form ectopic anterior clusters. syg-1 encodes an immunoglobulin superfamily protein that acts in the presynaptic HSNL axon. SYG-1 protein is localized to the site of future synapses, where it initiates synapse formation and localizes synaptic connections in response to the epithelial signal. SYG-1 is related to Drosophila IrreC and vertebrate NEPH1 proteins, which mediate cell-cell recognition in diverse developmental contexts.
authors.affiliation: Department of Anatomy, Howard Hughes Medical Institute, Box 0452, University of California, San Francisco, San Francisco, CA 94143, USA.
authors.forename: Kang
authors.initials: K
authors.lastname: Shen
authors.forename: Cornelia I
authors.initials: CI
authors.lastname: Bargmann
mesh_terms: D000818:Animals; D019521:Body Patterning / Q000235:genetics; D017173:Caenorhabditis elegans / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000302:isolation & purification*; D002450:Cell Communication / Q000235:genetics; D002451:Cell Compartmentation / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics*; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D005260:Female; D007136:Immunoglobulins / Q000235:genetics / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000302:isolation & purification*; D009420:Nervous System / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D009434:Neural Pathways / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D017729:Presynaptic Terminals / Q000378:metabolism* / Q000648:ultrastructure; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D013569:Synapses / Q000378:metabolism / Q000648:ultrastructure; D013572:Synaptic Vesicles / Q000378:metabolism / Q000648:ultrastructure; D014844:Vulva / Q000166:cytology / Q000196:embryology / Q000294:innervation
chemical_list: D029742:Caenorhabditis elegans Proteins; D007136:Immunoglobulins; D009419:Nerve Tissue Proteins; C473474:SYG-1 protein, C elegans