Elucidating the Role of Slitrk1 in the Morphology of Mechanosensory Neurons in the Developing Zebrafish Spinal Cord
The Slitrks are a novel gene family associated with neurite outgrowth, neuronal survival, and synapse formation. Mutations in Slitrks have been associated with neuropsychiatric disorders, such as Tourette’s syndrome, OCD spectrum disorders, and trichotillomania. Slitrk1’s expression pattern in the developing zebrafish nervous system suggests potential involvement in the development and function of Rohon-Beard (RB) neurons. The RB neurons are transient mechanosensory neurons that innervate the trunk skin and some of the first neurons to sense information from the environment. We are examining potential roles of Slitrk1 on RB neurons in the developing zebrafish spinal cord. To investigate Slitrk1 function, antisense morpholino oligonucleotides (AMOs) are used to knock down the Slitrk1 gene and study the effects. These AMOs are delivered by microinjection at the 1-4 cell stage of zebrafish embryos. Chordin AMO serves as the positive control. Embryos that lack the chordin protein produced a distinct phenotype (deformed tail), demonstrating the success of microinjections. The chordin phenotype has been effective through many trials. In addition, the process of microinjecting embryos at the early stages did not cause morphological abnormalities or differences in survival rates. To visualize RB neurons, immunostaining was performed at 48 hours post fertilization (hpf) with a mouse anti-acetylated α-tubulin primary antibody, which stains the RB neurons. Confocal microscopy revealed RB neurons in immunostained zebrafish embryos. The number and location of the RB neurons will be recorded and analyzed using appropriate statistical analyses. In order to examine potential behavioral consequences of knocking down Slitrk1 protein, a locomotor assay will be conducted at 48 and 72 hpf to assay. This study will provide some insight into potential roles of Slitrk1.