INVESTIGATING THE ROLE OF DLX5 AND FOXG1 IN THE NEURAL DEVELOPMENT OF A MONOGAMOUS SPECIES

Convict Cichlids (Amatitlania sp.), a fish species commonly used as a model for pair-bonding, display mutual cohabitation, defense of shelter, partner preference, and biparental care. It is well documented that the mescorticolimbic dopaminergic reward pathway's neural structures requiring GABA-signalling and neuropeptides oxytocin and arginine-vasopressin have critical roles in regulating pair-bonding behavior. Foxg1 and Dlx5 are transcription factors that are expressed in forebrain compartments during development, which develop into the biological architecture of the mesocorticolimbic system. GABAergic neurons, which express ventrally during development undergo dorsal migration to form disinhibitory connections with dopaminergic neurons in the ventral tegmental area (VTA) of Convict Cichlids. These neurons might find other targets under different morphological conditions such as within the characteristic promiscuous phenotype of the developing Zebrafish (Danio rerio). For this reason, we suspect that interspecies differences in expression of transcription factors during neurogenesis might contribute to the evolutionary divergent behavioral presentation in adulthood, such as that required for partnership. Dlx5 and Foxg1 gene expression could be partly responsible for development of morphological differences during development and later neuronal migrations of distinct elements in the reward pathway responsible for complex decision-making required for pair-bond maintenance. We will use in situ hybridization to visualize these genes during embryonic neurogenesis to compare neural development in Danio rerio (DR), a non-monogamous fish species, to Amatitlania sp. (AZ), our monogamous model. By visualizing these genes in both DR and AZ we will show differential expression of Dlx5 and Foxg1 in embryo concordant with those behavioral differences.