Evolution of Nematode Development
November 2011: Marie-Anne Felix and her group moved to the Institute of Biology of the Ecole Normale Supérieure. Their new page is on http://www.ibens.ens.fr/spip.php?article256&lang=en
We are studying the development and evolution of a major model system in developmental biology, the vulva of the nematode worm Caenorhabditis elegans. We are particularly interested in the developmental robustness of this organ when faced with random noise, environmental variations or mutations, and in its evolution in C. elegans and other closely related nematodes.
During vulval formation, a centered pattern of three developmental cell fates is specified within a row of six cells, based on a robust intercellular signaling network that produces an invariant output of fates. The correct fate pattern is required for formation of a normal vulva, and consequently for egg-laying and copulation.
We are investigating the precision and evolution of the developmental mechanisms that underlie vulva formation in different nematode species and wild isolates of C. elegans , and their evolvability (capacity to evolve) upon random mutation. Amongst our results the following are particularly striking :
whereas the final spatial pattern of vulval precursor cell fates is robust and invariant, the developmental mechanisms that lead to this cell fate pattern vary between species and even within a species, depending on the genetic background and environmental conditions;
the relative evolvability of the different vulval characters itself evolves, which may explain the variations within a species and between closely related species.
The genetic structure of a population (its outcrossing rate, the occurrence of population bottlenecks, etc.) influences the available phenotypic variation and is therefore relevant to understanding phenotypic evolution. Moreover, C. elegans presents an unusual mode of reproduction with self-fertilising hermaphrodites and facultative males, and can thus reproduce either by selfing or by outcrossing. We are examining natural populations of C. elegans to understand their lifestyle outside the laboratory, and especially their rate of outcrossing and population structure.
Selection of Publications
Braendle, C. and Félix, M.-A. (2008). Plasticity and errors of a robust developmental system in different environments. Dev. Cell 15, 714-724. Full text
Milloz, J., Duveau, F., Nuez, I. and Félix, M.-A. (2008). Intraspecific evolution of the intercellular signaling network underlying a robust developmental system. Genes Dev. 22, 3064-3075. Full text
Barrière, A. and Félix, M.-A. (2007). Temporal dynamics and linkage disequilibrium in natural C. elegans populations. Genetics 176, 999-1011. Full text
Félix, M.-A. (2007). Cryptic quantitative evolution of the vulva intercellular network in Caenorhabditis. Curr. Biol. 17, 103-114. Full text
Barrière, A. and Félix, M.-A. (2005). High local genetic diversity and low outcrossing rate in Caenorhabditis elegans natural populations. Curr. Biol. 15, 1176-1184. Full text
Dernière modification 23/11/2012