Honors Theses
Date of Award
2015
Document Type
Undergraduate Thesis
Department
Chemistry and Biochemistry
First Advisor
Susan Pedigo
Relational Format
Dissertation/Thesis
Abstract
Neural Cadherin (NCAD) is one of three Type 1 vertebral classical cadherins that function as the primary transmembrane component in cell-to-cell interactions at adherens junctions. Adhesive interactions mediated by this protein are calcium dependent with three calcium-binding sites between each of its five extracellular domains. NCAD is very important in many cell-to-cell interactions because of its function in development and in immune and neurological synapses. Generally, in vitro studies of calcium dependent dimerization of NCAD are conducted in a nonphysiological buffer (NaCl + HEPES: SEC buffer). In order to study dimerization in more physiologically relevant conditions, I created a synthetic blood plasma (SBP) that more closely mimics the conditions in the extracellular space in the human body. Spectroscopic and chromatographic studies have shown that the stability, calcium binding affinity and dimerization properties depend upon the buffer conditions. Thermal denaturation studies show that stability of NCAD12 in SBP buffer is similar to that in SEC buffer. Calcium binding studies show precipitation in SBP buffer, most likely due to the precipitation of calcium phosphate. The data also appear to show competition between Ca2+ and Mg2+ in SBP buffer. Analytical SEC studies indicate that there is a lower affinity of dimerization in SBP buffer compared to that in SEC buffer. Further studies titrating NCAD12 with magnesium to determine its effects on dimerization without the presence of calcium are necessary to understand the effect that magnesium has on dimerization. In summary, the more complex environment in which dimerization occurs in vivo impacts the apparent properties of NCAD.
Recommended Citation
Treadway, Brent, "Effects of Synthetic Blood Plasma on Calcium Dependent Dimerization of NCAD12" (2015). Honors Theses. 139.
https://egrove.olemiss.edu/hon_thesis/139
Accessibility Status
Searchable text