The Record 2009 - Keble College - University of Oxford

Keble College: The Record 2009
Fellows’ Work in Progress
Investigating worm immunity
Jonathan Hodgkin, Professorial
Fellow and Professor of Genetics
Why study a tiny worm? The question is reasonable, especially
when the worm concerned is insignificant, barely visible
and harmless, causing no disease in humans, animals or
plants. Indeed, the animal is so unremarkable that it does
not even have a common name, only the rather forbidding
systematic title of Caenorhabditis elegans, which is almost always
abbreviated to the more familiar C. elegans. It is a kind of
nematode, or roundworm, and is one species among a vast
group of invertebrates that pervade the biosphere but mostly
go unnoticed. C. elegans, however, has become the most famous
of all nematodes, and there are now several thousand scientists
whose working lives are devoted to investigating the different
facets of its biology.
I have spent most of my research career working on and
with C. elegans, initially to explore problems in neurobiology,
developmental biology and sex determination, and more
recently to investigate how this simple animal is able to
recognize and fight off bacterial pathogens. About forty years
ago, an adventurous molecular biologist called Sydney Brenner
chose to exploit C. elegans as a good experimental organism
for investigating complex biological problems. The basics of
molecular biology — the role of DNA, the central dogma and
the genetic code — had been worked out using viruses and
bacteria, but bacteria do not develop elaborate multicellular
structures and do not have nervous systems, so they can’t be
used for studying developmental biology or behaviour. C. elegans
does have these features, with nerves and differentiated tissues,
but it has only about a thousand cells in all, so it is a sort of
minimalist animal. It’s also transparent throughout its lifecycle
and therefore ideal for microscopic examination. The worm is
also very easy to grow, and has a generation time of only three
days, which makes it wonderful for doing genetic experiments.
Brenner’s vision of what could be done with C. elegans was
inspirational to many young scientists, myself included, and
resulted in a new and still expanding field of investigators,
who study many different phenomena but are united by using
the worm as an experimental system. More than 600 research
groups around the world now study C. elegans intensively, and
every year another fifty or more are added to the roster. Two
Nobel prizes (in Physiology or Medicine) and part of a third
(in Chemistry) have so far been awarded for discoveries made
using this experimental system.
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