Habenular Axons in cxcl12a mutant Zebrafish

The habenula is a small bilateral structure in the brain. The habenula is involved in pain, reproductive behavior, sleep-wake cycle, nutrition, and stress. Cxcr4b is a chemokine receptor that aids in the orientation of axons from the habenula. Chemokines are a small group of cytokines secreted by cells that aid in directional movement. The Cxcl12a, cytokine ligand, is responsible for the regeneration of the fins, nervous system development, and regulation of cell migration. The focus of this research is to see if the absence of cxcl12a would disrupt the progression of the axons from the habenula to the midbrain. We are crossing fish that carry a mutation in cxcl12a and also express green fluorescent protein (GFP) in the habenula and its axons. At 5 days post fertilization (dpf) we image the habenula and its axons. Then a PCR is performed to genotype larvae that were imaged. We then compare habenular axons of mutant larvae to axons of wild type and heterozygous siblings. We hypothesize that the absence of cxcl12a will disrupt the progression of the axons from the habenula to the midbrain.