title: The SAX-3 receptor stimulates axon outgrowth and the signal sequence and transmembrane domain are critical for SAX-3 membrane localization in the PDE neuron of C. elegans.
abstract: SAX-3, a receptor for Slit in C. elegans, is well characterized for its function in axonal development. However, the mechanism that regulates the membrane localization of SAX-3 and the role of SAX-3 in axon outgrowth are still elusive. Here we show that SAX-3::GFP caused ectopic axon outgrowth, which could be suppressed by the loss-of-function mutation in unc-73 (a guanine nucleotide exchange factor for small GTPases) and unc-115 (an actin binding protein), suggesting that they might act downstream of SAX-3 in axon outgrowth. We also examined genes related to axon development for their possible involvement in the subcellular localization of SAX-3. We found the unc-51 mutants appeared to accumulate SAX-3::GFP in the neuronal cell body of the posterior deirid (PDE) neuron, indicating that UNC-51 might play a role in SAX-3 membrane localization. Furthermore, we demonstrate that the N-terminal signal sequence and the transmembrane domain are essential for the subcellular localization of SAX-3 in the PDE neurons.
authors.affiliation: The Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.forename: Pu
authors.initials: P
authors.lastname: Pu
authors.forename: Weidong
authors.initials: W
authors.lastname: Le
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001369:Axons / Q000378:metabolism* / Q000502:physiology; D017173:Caenorhabditis elegans / Q000166:cytology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000378:metabolism; D008856:Microscopy, Fluorescence; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000502:physiology; D034622:RNA Interference; D060888:Real-Time Polymerase Chain Reaction; D011971:Receptors, Immunologic / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D000097905:Roundabout Proteins
chemical_list: D029742:Caenorhabditis elegans Proteins; D017931:DNA Primers; D049452:Green Fluorescent Proteins; D009419:Nerve Tissue Proteins; D017346:Protein Serine-Threonine Kinases; D011971:Receptors, Immunologic; D000097905:Roundabout Proteins; C112443:UNC-51 protein, C elegans