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C. elegans

Caenorhabditis elegans
research

Evo-devo using nematodes

My research mostly concerns the genetic control of growth in the nematode Caenorhabditis elegans. This is the minute worm which formed the basis of the studies for which Sulston, Horvitz and Brenner won the Nobel Prize in 2002. We are particularly interested in how several molecular signalling pathways control the size to which the worm grows (about 1 mm long). We are studying the TGF-beta (DBL-1) pathway, a molecule which is secreted by the worm's ventral nerve cord and appears to act rather like growth hormone. We are investigating the genes that are the target of this pathway, how it influences the cells of growing worms, the size differences between the sexes (hermaphrodite worms are larger than males), and the way in which it mediates signals from the environment. We are also interested in another, quite different, growth control system that we identified in 2002: one that emanates from the worm's gonad. To study these problems we use a variety of standard molecular techniques, including screening for gigantism and dwarfism mutants, and some that are more unique to worms such as laser microsurgery.

Our research is not, however, merely motivated by understanding growth in C. elegans. We also want to understand the genetic basis of body size evolution in nematodes. We have a zoo of about 50 species of free-living nematodes that we keep in the laboratory much as we keep C. elegans (on petri dishes eating E. coli), some of which are larger than C. elegans itself. We believe that the TGF-beta pathway is involved in these evolutionary differences.

We are also interested in computational models of nematode development. Using software developed by collaborators at DKFZ, Heidelberg and Houston, we are analysing the lineage and three-dimensional topology of embryonic development.


Transmissible Cancers

With collaborators at Silwood Park and ICR, London, we are also working on dog veneral cancer, a bizarre neoplasm that has taken up life as a single-celled mammalian pathogen. It's found in dogs throughout the world, and we are tracing its evolution and spread using molecular markers. We are also trying to find out how these cells have adapted, that is, how they have become more parasite-like and less dog-like.

Genitals of a bitch afflicted with Canine Transmissible Venereal Sarcoma (CVTS)
Genitals of a bitch afflicted with Canine Transmissible Venereal Sarcoma (CVTS)

The evolution of music

All humans sing. But they don't usually just make songs up; they learn them from other people. This means that song styles evolve rather as languages do. Inspired by the early work of Alan Lomax, a pioneer of ethnomusicology - the study of non-Western music - we are attempting to use evolutionary algorithms to trace out the history of song styles. We are analysing thousands of songs from around the world to find out how they are related to each other. Perhaps we can even identify some of the features of the very first song sung by humans. Our collaborators on this project are the musician Brian Eno and the Alan Lomax Foundation in New York.

Orpheus charming the animals.  Roman Mosaic, 350 AD
Orpheus charming the animals. Roman Mosaic, ˜350 AD


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