Synaptic Specificity Is Generated by the Synaptic Guidepost Protein SYG-2 and Its Receptor, SYG-1

Howard Hughes Medical Institute, Department of Anatomy, The University of California, San Francisco, San Francisco, CA 94143, USA.
Cell (Impact Factor: 32.24). 04/2004; 116(6):869-81. DOI: 10.1016/S0092-8674(04)00251-X
Source: PubMed


Synaptic connections in the nervous system are directed onto specific cellular and subcellular targets. Synaptic guidepost cells in the C. elegans vulval epithelium drive synapses from the HSNL motor neuron onto adjacent target neurons and muscles. Here, we show that the transmembrane immunoglobulin superfamily protein SYG-2 is a central component of the synaptic guidepost signal. SYG-2 is expressed transiently by primary vulval epithelial cells during synapse formation. SYG-2 binds SYG-1, the receptor on HSNL, and directs SYG-1 accumulation and synapse formation to adjacent regions of HSNL. syg-1 and syg-2 mutants have defects in synaptic specificity; the HSNL neuron forms fewer synapses onto its normal targets and forms ectopic synapses onto inappropriate targets. Misexpression of SYG-2 in secondary epithelial cells causes aberrant accumulation of SYG-1 and synaptic markers in HSNL adjacent to the SYG-2-expressing cells. Our results indicate that local interactions between immunoglobulin superfamily proteins can determine specificity during synapse formation.

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    • "Development | Supplementary Material Table S2. Alleles used in this study mutant allele reference alp-1(ok820) (Han and Beckerle, 2009) atn-1(ok84) (Moulder et al., 2010) bar-1(ga80) (Eisenmann et al., 1998) dlk-1(km12) (Bounoutas et al., 2009) dyc-1(cx32) (Gieseler et al., 2000) glh-1(gk100) (Lall et al., 2005) hmp-1(fe4) (Pettitt et al., 2003) ina-1(gm144) (Baum and Garriga, 1997) ina-1(gm39) (Baum and Garriga, 1997) kin-32(ok166) (Cram et al., 2008) lim-8(ok941) (Qadota et al., 2007) lim-9(gk106) (Qadota et al., 2007) mkk-4(ok1545) (Bounoutas et al., 2009) pat-3(st564) (Poinat et al., 2002) pat-4(st551) (Mackinnon et al., 2002) pmk-3(ok169) (Nakata et al., 2005) pry-1(mu38) (Korswagen et al., 2002) scpl-1(ok1080) (Qadota et al., 2008) syg-1(ky652) (Shen and Bargmann, 2003) syg-2(ky671) (Shen et al., 2004) uig-1(ok884) (Hikita et al., 2005) unc-15(e73) (Deitiker and Epstein, 1993) unc-34(e315) (Fleming et al., 2010) unc-54(e190) (Waterston et al., 1982) unc-97(su110) (Hobert et al., 1999) unc-98(su130) (Mercer et al., 2003) unc-112(r367) (Rogalski et al., 2000) "
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