The divergent C. elegans ephrin EFN-4 functions inembryonic morphogenesis in a pathway independent of the VAB-1 Eph receptor.
The C. elegans genome encodes a single Eph receptor tyrosine kinase, VAB-1, which functions in neurons to control epidermal morphogenesis. Four members of the ephrin family of ligands for Eph receptors have been identified in C. elegans. Three ephrins (EFN-1/VAB-2, EFN-2 and EFN-3) have been previously shown to function in VAB-1 signaling. We show that mutations in the gene mab-26 affect the fourth C. elegans ephrin, EFN-4. We show that efn-4 also functions in embryonic morphogenesis, and that it is expressed in the developing nervous system. Interestingly, efn-4 mutations display synergistic interactions with mutations in the VAB-1 receptor and in the EFN-1 ephrin, indicating that EFN-4 may function independently of the VAB-1 Eph receptor in morphogenesis. Mutations in the LAR-like receptor tyrosine phosphatase PTP-3 and in the Semaphorin-2A homolog MAB-20 disrupt embryonic neural morphogenesis. efn-4 mutations synergize with ptp-3 mutations, but not with mab-20 mutations, suggesting that EFN-4 and Semaphorin signaling could function in a common pathway or in opposing pathways in C. elegans embryogenesis.
Chin-Sang
Ian D
ID
Department of Molecular, Cell, and Developmental Biology, Sinsheimer Laboratories, University of California, Santa Cruz 95064, USA.
Moseley
Sarah L
SL
Ding
Mei
M
Harrington
Robert J
RJ
George
Sean E
SE
Chisholm
Andrew D
AD
D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000166:cytology / Q000196:embryology* / Q000502:physiology; D029742:Caenorhabditis elegans Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D036342:Ephrins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004843:Epistasis, Genetic; D017930:Genes, Reporter; D006801:Humans; D007814:Larva / Q000033:anatomy & histology / Q000502:physiology; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D009024:Morphogenesis; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009420:Nervous System / Q000254:growth & development; D030781:Organisms, Genetically Modified; D016415:Sequence Alignment; D015398:Signal Transduction / Q000502:physiology*
D029742:Caenorhabditis elegans Proteins; D018797:Cell Cycle Proteins; C470369:EFN-4 protein, C elegans; D036342:Ephrins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C405025:mab-20 protein, C elegans