| Description |
The primary goal of neuroscience research is to understand how the brain and nervous system function, and ultimately to produce a biological explanation of mental processes such as learning, behavior, and consciousness. To this end, neuroscientists dissect the brain and study nervous tissue on cellular and molecular levels. One important molecular process that has significant implications for higher brain function is the homeostatic control of calcium ions within nerve cells. Mediating many fundamental neuronal processes, calcium ions are kept at low intracellular concentrations by membrane pumps and exchangers, intracellular stores, and calcium binding proteins. Calretinin belongs to the EF-hand family of calcium binding proteins whose primary function is to bind and buffer intracellular calcium ions. The concentration and the precise localization of calcium buffering proteins significantly influence the effects that such proteins have on calcium signaling transients. Calretinin has been immunohistochemically mapped to many sensory neurons in the nervous system, and its concentration levels have been shown to increase in the brainstem auditory neurons of the chick nucleus magnocellularis (NM) during development. Recent evidence has shown that calretinin concentration in NMs undergoes a dramatic developmental redistribution from diffuse throughout the cytoplasm in early stages to concentrated under the plasma membrane in later stages. I confirmed these results using biochemical analysis of membrane and cytosolic fractions and asked whether this developmental redistribution of calretinin is influenced by calcium, cytoskeleton structure, or membrane associations. Based on my results, I predict that this translocation of calretinin during development significantly affects both spatial and temporal aspects of calcium signaling. |
