Sex-Specific Regulation of GABAergic Neurons
2008 Seed Grant
Ilya Ruvinsky, Ph.D.
University of Chicago
Males and females of most species display pronounced sexual dimorphisms. These extend to
the nervous systems and include distinct anatomical and functional features, which are
ultimately manifested in behavioral differences (Kandel, 2000). It is essential to understand the
molecular mechanisms responsible for generating and maintaining these sex-specific
differences. We are developing a system in which these mechanisms can be studied in a
framework of a well-established model species and a well-characterized group of neurons.
The GABAergic neurons of Caenorhabditis elegans have been studied in hermaphrodites (these
animals are genetically equivalent to females of other species), but no in males. We have
discovered that the GABAergic system of C.elegans males differs from that of hermaphrodites
in two important aspects. First, a number of neurons that are unique to males utilize GABA as a
neurotransmitter. Second, several neurons that are common to both sexes utilize GABA in
males, but not hermaphrodites. Based on these preliminary findings, we propose a series of
experiments to document the extent of sex-specific dimorphism in the GABAergic system of C.
Elegans and to investigate the molecular mechanisms responsible for these differences.