| |
| author |
Stefanie DeFronzo
| | title |
Worms on the Brain: The Role of Autism-Related Genes nlg-1 and nrx-1 in Thermotactic and Chemotactic Behavior of C. elegans
| | abstract |
Neuroligin (NLG) and neurexin (NRX) are molecules involved in synaptic
function. Previous studies have reported that Caenorhabditis elegans (C. elegans)
neurexin directs neuronal connectivity through action at synapses with partnering neurons
and muscles. This study employs C. elegans as a model system to study behavioral
defects associated with mutations in the neuroligin and neurexin genes, which in humans
have been found to be linked to various autism spectrum disorders (ASDs). Carrying a
single neuroligin and neurexin gene (nlg-1 and nrx-1 respectively), C. elegans can be
mutated in such genes and the resulting phenotypic responses can be observed. The focus
of this study is to observe the thermotactic and chemotactic behavior of nlg- and nrx-
disrupted strains of C. elegans versus the wildtype N2 strain in order to obtain insight
into the implications of these mutations and the role that these genes play in
neurodevelopment. Using adapted thermotaxis and chemotaxis assays, wildtype N2 and
mutants VC228 (nlg-1, ok259), SG1(nrx-1, dx1), and MLB1316 (nlg-1, ok259; nrx-1,
dx1) were observed for thermotactic and chemotactic behavioral differences. There was
found to be a significant difference between the thermotactic behavior of both single and
double mutant nlg-1 and nrx-1 worms compared to that of wildtype N2 worms (P<0.05).
Additionally, there appeared to be a difference in thermosensory ability between worms
raised at 16°C and those raised at 25°C. All control and mutant strains were repelled by
the chemorepellent 1-octanol, but nrx-1 mutants were notably less repelled than other
strains. The conclusions of this study allow increased understanding of the
neurodevelopmental processes occurring within C. elegans, implying that thermosensory
and chemosensory behavior are neuronally connected. Our findings also support C.
elegans as a good model to study neurodevelopment and human neurological disorders
like ASD.
| | school |
The College of Liberal Arts, Drew University
| | degree |
B.A. (2020)
|
| advisor |
Marvin Bayne
|
| full text | SDeFronzo.pdf |
| |
