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Manipulation of Ploidy in Caenorhabditis elegans
Published on: March 15, 2018
Roles for mating and environment in C. elegans sex determination
Veena Prahlad1, Dave Pilgrim, Elizabeth B Goodwin
1Genetics Department, University of Wisconsin, 445 Henry Mall, Madison, WI 53706, USA.
Science (New York, N.Y.)
|November 8, 2003
Summary
Sex determination in C. elegans is not fixed at fertilization. Sexual reproduction allows XX larvae to develop as males, demonstrating postembryonic developmental flexibility for environmental adaptation.
Area of Science:
- Developmental biology
- Genetics
- Evolutionary biology
Background:
- The nematode C. elegans typically exhibits two sexes: XX hermaphrodites and XO males, determined by the X chromosome-to-autosome ratio at fertilization.
- This sex determination is widely considered a fixed, irreversible process occurring early in embryonic development.
Purpose of the Study:
- To investigate whether sex and genotype determination in C. elegans can be altered after embryonic development.
- To determine the role of sexual reproduction in this potential developmental plasticity.
Main Methods:
- Culturing C. elegans (XX) larvae derived from both mating (male x hermaphrodite) and self-fertilization (hermaphrodite x hermaphrodite) under specific bacterial metabolite conditions.
- Observing and analyzing sex and X chromosome content in postembryonic larval stages.
Main Results:
- XX larvae resulting from mating, when exposed to specific bacterial metabolites, can develop into males and lose an X chromosome.
- XX larvae produced through hermaphrodite self-fertilization do not exhibit such sex or genotypic alterations under the same conditions.
- This indicates that sexual reproduction is a prerequisite for postembryonic developmental flexibility.
Conclusions:
- The study challenges the paradigm of irreversible sex determination at fertilization in C. elegans.
- Sexual reproduction enhances developmental plasticity in progeny, enabling adaptation to changing environmental conditions.
- This flexibility may be a key evolutionary advantage conferred by sexual reproduction.
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