TABLE CONTENTS

Expression Profiling and the Search for Parasitism Genes in Animal
Parasite Nematodes
Grant, W. (1) & M. Viney (2)
(1) Genetics Department, La Trobe University, Melbourne; (2) School of Biological Sciences, Bristol
University, Bristol
The nature of the genetic basis of parasitism in nematodes, and the identity of “parasitism
genes” that may have been subjected to selection during the evolution of parasitism, remain
unknown. Identifying those genes is of both academic and practical significance.
Furthermore, the hypothesis that parasitism has most likely evolved independently several
times in nematodes raises the question whether these separate events have followed similar or
different paths i.e. has the same set of parasitism genes been selected in different parasites? In
animal parasites, a longstanding hypothesis is that the dauer pathway from free-living
nematodes played an important role in the evolution of parasitism. We have examined this
hypothesis by cloning and characterising the expression of some of the key dauer genes from
parasites of the genera Strongyloides and Parastrongyloides, and have sought more broadly
for candidate parasitism genes by microarray comparisons of gene expression between the
parasitic and non-parasitic life cycles. In general, these data support a role for dauer genes but
have so far failed to discover novel genes that may required for parasitism in these two
genera.
5 th International Congress of Nematology, 2008 112