Faculty mentor/PI email address
ellisre@rowan.edu
Is your research Teaching and Learning based?
1
Keywords
Molecular biology, Gli proteins, EMS Screening, Backcrossing, Mapping Strains
Date of Presentation
5-6-2026 12:00 AM
Poster Abstract
BACKGROUND:
Gli proteins are conserved transcription factors that regulate cell fate, proliferation, and patterning. In Caenorhabditis briggsae, the Gli protein TRA-1 functions as the terminal regulator of the sex-determination pathway to control sexual development. These nematodes lack Hedgehog signaling, so TRA-1 is regulated by other factors. The missense mutation tra-1(v48) disrupts TRA-1 activator function, resulting in complete feminization of XX animals, which would otherwise be hermaphrodites.
HYPOTHESIS:
Suppressor screens using tra-1(v48) mutants will identify novel cofactors required for TRA-1–mediated Gli activation and spermatogenesis.
METHODS:
Ethyl methanesulfonate (EMS) mutagenesis was performed on tra-1(v48) strains to induce random mutations. Dominant suppressors were identified by crossing mutagenized males with tra-1(v48); unc-7 females and screening the F1 progeny for self-fertile hermaphrodites. Candidate suppressors were backcrossed to remove background mutations and will be mapped using SNP (indel) markers between AF16 and HK104 strains.
RESULTS:
Screening 267 haploid genomes identified two semi-dominant suppressors, v557 and v558, which restore self-fertility in tra-1(v48) XX animals. Both also exhibit recessive lethality. Backcrossing is nearly complete, with v557 reaching 5 generations, while v558 is at 3 generations.
CONCLUSION:
TRA-1 activator function can be restored through secondary mutations, revealing previously unrecognized regulators of Gli activity. These regulators appear to be essential proteins. Ongoing mapping and whole-genome sequencing will identify these cofactors and provide insight into conserved mechanisms underlying development and disease.
Disciplines
Animals | Genetics and Genomics | Medicine and Health Sciences
Included in
Identification of Genes Regulating the Gli protein TRA-1 in Caenorhabditis briggsae Through a Genetic Suppressor Screen
BACKGROUND:
Gli proteins are conserved transcription factors that regulate cell fate, proliferation, and patterning. In Caenorhabditis briggsae, the Gli protein TRA-1 functions as the terminal regulator of the sex-determination pathway to control sexual development. These nematodes lack Hedgehog signaling, so TRA-1 is regulated by other factors. The missense mutation tra-1(v48) disrupts TRA-1 activator function, resulting in complete feminization of XX animals, which would otherwise be hermaphrodites.
HYPOTHESIS:
Suppressor screens using tra-1(v48) mutants will identify novel cofactors required for TRA-1–mediated Gli activation and spermatogenesis.
METHODS:
Ethyl methanesulfonate (EMS) mutagenesis was performed on tra-1(v48) strains to induce random mutations. Dominant suppressors were identified by crossing mutagenized males with tra-1(v48); unc-7 females and screening the F1 progeny for self-fertile hermaphrodites. Candidate suppressors were backcrossed to remove background mutations and will be mapped using SNP (indel) markers between AF16 and HK104 strains.
RESULTS:
Screening 267 haploid genomes identified two semi-dominant suppressors, v557 and v558, which restore self-fertility in tra-1(v48) XX animals. Both also exhibit recessive lethality. Backcrossing is nearly complete, with v557 reaching 5 generations, while v558 is at 3 generations.
CONCLUSION:
TRA-1 activator function can be restored through secondary mutations, revealing previously unrecognized regulators of Gli activity. These regulators appear to be essential proteins. Ongoing mapping and whole-genome sequencing will identify these cofactors and provide insight into conserved mechanisms underlying development and disease.