The pax-3 gene is involved in vulva formation in Pristionchus pacificus and is a target of the Hox gene lin-39.
The Hox gene lin-39 plays a crucial role in the establishment of the nematode vulva equivalence group. Mutations in lin-39 in Caenorhabditis elegans and Pristionchus pacificus result in a vulvaless phenotype because presumptive vulva precursor cells adopt non-vulval fates. Interestingly, the non-vulval fate of anterior and posterior epidermal cells differs between Caenorhabditis and Pristionchus; in C. elegans, non-vulval cells fuse with the hypodermis, whereas, in P. pacificus, they die as a result of programmed cell death. C. elegans lin-39 (Cel-lin-39) indirectly controls the cell fusion gene eff-1 by regulating the GATA transcription factors egl-18 and elt-6. In P. pacificus, the genetic context of its lin-39 (Ppa-lin-39) function was unknown. Here, we describe the isolation and characterization of gev-2, a second generation-vulvaless mutant in P. pacificus. We show that gev-2 is the Ppa-pax-3 gene and that it has distinct functions in the cell fate specification of epidermal cells. Whereas Ppa-pax-3 regulates cell survival of the presumptive vulval precursor cells, it controls cell death of posterior epidermal cells. Molecular studies indicate that Ppa-pax-3 is a direct target of Ppa-LIN-39. Thus, we describe the first specific developmental defect of a nematode pax-3 gene and our data reveal different regulatory networks for the specification of the vulva equivalence group.
Yi
Buqing
B
Max-Planck Institute for Developmental Biology, Department for Evolutionary Biology, Spemannstrasse 37, D-72076 Tübingen, Germany.
Sommer
Ralf J
RJ
D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D017209:Apoptosis / Q000235:genetics; D001483:Base Sequence; D029742:Caenorhabditis elegans Proteins / Q000235:genetics; D004625:Embryo, Nonmammalian; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017238:Genes, Helminth; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000235:genetics; D008297:Male; D008954:Models, Biological; D008969:Molecular Sequence Data; D009348:Nematoda / Q000196:embryology* / Q000235:genetics / Q000254:growth & development; D051761:Paired Box Transcription Factors / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D012733:Sex Differentiation / Q000235:genetics; D014844:Vulva / Q000196:embryology* / Q000254:growth & development
D029742:Caenorhabditis elegans Proteins; D018398:Homeodomain Proteins; D051761:Paired Box Transcription Factors; C108673:lin-39 protein, C elegans