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Updated: May 7, 2026
10:07
Measuring Sperm Guidance and Motility within the Caenorhabditis elegans Hermaphrodite Reproductive Tract
Published on: June 6, 2019
Evolutionary change within a bipotential switch shaped the sperm/oocyte decision in hermaphroditic nematodes
Yiqing Guo1, Xiangmei Chen, Ronald E Ellis
1Department of Molecular Biology, Rowan-SOM and the UMDNJ-SOM, B303 Science Center, Stratford, New Jersey, United States of America.
Plos Genetics
|October 8, 2013
Summary
The sex-determination protein TRA-1 is bipotential, acting as a switch. Its co-factor TRR-1 helps regulate this switch, with its function evolving rapidly between species.
Area of Science:
- Genetics
- Developmental Biology
- Evolutionary Biology
Background:
- Bipotential transcription factors can activate or repress targets based on upstream signals.
- Previous studies suggested the sex-determination protein TRA-1 might be bipotential.
Purpose of the Study:
- Confirm TRA-1's bipotential nature by identifying a co-factor.
- Investigate how the structure of this bipotential switch evolves.
Main Methods:
- Utilized null mutants and RNA interference in C. briggsae.
- Performed epistasis tests and RT-PCR.
- Analyzed gene expression and developmental phenotypes.
Main Results:
- C. briggsae TRR-1 is essential for spermatogenesis and works with the Tip60 Histone Acetyl Transferase complex.
- TRR-1 regulates Cbr-fog-3 expression and the sperm/oocyte decision via TRA-1, confirming TRA-1's bipotentiality.
- TRR-1 also controls male tail development, with both regulatory branches influencing TRA-1 activity.
- Evolutionary analysis revealed significant shifts in the interplay between TRR-1 and FEM regulatory branches across species.
Conclusions:
- TRA-1 is confirmed as a bipotential regulator.
- The relationship between regulatory components of the TRA-1 switch evolves rapidly.
- Species utilize alternative mechanisms to achieve similar developmental outcomes through flexible regulatory networks.
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