2011 Theses Doctoral

Neuronal Laterality in Caenorhabditis elegans: Morphological and Functional Aspects

Goldsmith, Andrew D.

The ASE neurons of C. elegans are an excellent model to study neuronal asymmetry. Lateralization with respect to their genetic fate and function has been well studied, but their more subtle asymmetries have not. This work describes three such asymmetries: that of amino acid gustation, associative learning, and morphological size. In the first two of these, I found a previously uncharacterized asymmetric neuronal response with respect to amino acid gustation, and expand on the known asymmetry with respect to associative salt learning. Most of this thesis focuses on a discovered size asymmetry in the ASE pair of neurons: characterizing it, providing a functional significance, and describing some of its genetic underpinnings. Size asymmetry and the mechanisms of overall neuron growth are not well-studied, but do have functional consequences in higher organisms. This work hopefully furthers our understandings of these processes and of neuronal development in general.