Extragenic suppressors of a dominant masculinizing her-1 mutation in C. elegans identify two new genes that affect sex determination in different ways.
The her-1 regulatory switch gene in C. elegans sex determination is normally active in XO animals, resulting in male development, and inactive in XX animals, allowing hermaphrodite development. The her-1(n695gf) mutation results in the incomplete transformation of XX animals into phenotypic males. We describe four extragenic mutations that suppress the masculinized phenotype of her-1(n695gf) XX. They define two previously undescribed genes, sup-26 and sup-27. All four mutations exhibit semidominance of suppression and by themselves have no visible effects on sex determination in otherwise genotypically wild-type XX or XO animals. Analysis of interactions with mutations in the major sex-determining genes show that sup-26 and sup-27 influence sex determination in fundamentally different ways. sup-26 appears to act independently of her-1 to negatively modulate synthesis or function of tra-2 in both XX and XO animals. sup-27 may play a role in X-chromosome dosage compensation and influence sex determination indirectly.
Manser
James
J
Department of MCD Biology, University of Colorado, Boulder, Colorado, USA.
Wood
William B
WB
Perry
Marc D
MD
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins; D004303:Dosage Compensation, Genetic; D016153:Genes, Suppressor / Q000502:physiology; D015801:Helminth Proteins / Q000235:genetics* / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D019849:Sex Determination Processes; D014157:Transcription Factors; D014960:X Chromosome
D029742:Caenorhabditis elegans Proteins; D004268:DNA-Binding Proteins; D015801:Helminth Proteins; D008565:Membrane Proteins; C079666:Sdc-3 protein, C elegans; D014157:Transcription Factors; C079744:her-1 protein, C elegans; C121025:tra-1 protein, C elegans; C076107:tra-2 protein, C elegans