Date of Award


Publication Type

Master Thesis

Degree Name



Biological Sciences


Barbara Zielinski




Spatial analysis of neuronal activation by assessing the localization of proteins upon an external stimulus has been well established. In particular, analysis of the expression of c-Fos protein has been widely used for investigating pathways of neural activity. In the current study, this approach was expanded to zebrafish by assessing Fos-like protein immunolocalization in the brain structures known to integrate olfactory sensory information, and to neural pathways that may link olfaction to locomotor control. The Fos-like protein was visualized in zebrafish brain tissue by western blot (sc-253) following amino acid exposure, and we found that it produced two bands at 64 and 77 kDa. These molecular weights were very similar to those seen in a previous study which probed for c-Fos protein in zebrafish tissue. We hypothesized that during exposure to amino acid odours, Fos-like immunoreactivity would be localized in brain regions that integrate olfactory sensory information, locomotor control centers, gustatory centers, and in neural pathways that link these regions. An increase in Fos-like immunoreactive cells was found in the olfactory bulb, and the lateral and posterior zones of the dorsal telencephalon. Both these telencephalic areas are target regions of the olfactory tracts. We did not find any significant changes in Fos-like immunoreactivity in the midbrain and hindbrain regions that we investigated. Some of these regions are responsible for locomotion and gustation, and therefore we did not find any integration of these sensory systems with the olfactory system using a Fos-like protein marker. This study is the first to apply Fos-like immunolocalization in zebrafish brain, and provides the potential for further applications of this tool for identifying neural activation during various sensory stimuli.