Medicine and Health Sciences Commons^™

Substrate And Regulation Of Mitochondrial Μ-Calpain, Aashish Joshi

University of Kentucky Doctoral Dissertations

μ -Calpain is localized to the mitochondrial intermembrane space. Apoptosisinducing factor (AIF), which executes caspase-independent cell death, is also localized to the mitochondrial intermembrane space. Following processing at the N-terminus, AIF becomes truncated (tAIF) and is released from mitochondria. The protease responsible for AIF processing has not been established. The same submitochondrial localization of mitochondrial μ-calpain and AIF gives support to the hypothesis that mitochondrial μ-calpain may be responsible for processing AIF. Atractyloside-induced tAIF release in rat liver mitochondria was inhibited by cysteine protease inhibitor MDL28170, but not by calpain inhibitors PD150606 or calpastatin. Moreover, μ-calpain immunoreactivity was difficult to …

The Interplay Between The Expression And Functions Of Wnt13 Isoforms During Apoptosis In Bovine Aortic Endothelial Cells, Tao Tang

University of Kentucky Doctoral Dissertations

Wnt proteins are crucial for development/homeostasis by controlling cell fate including apoptosis (Moon RT et al. 1997). Three humanWnt13 isoforms were identified: the secreted Wnt13A, mitochondrial Wnt13B, and nuclear Wnt13C forms; and nuclear Wnt13 had an increased sensitivity to LPS/TNF-induced apoptosis in primary endothelial cells (EC); both Wnt13B and C mRNA contain two start codons (AUG+1 and +74), but the same protein encoded from AUG+74 by Wnt13C was expressed lower than Wnt13B (Struewing IT et al.2006). We hypothesize that during EC apoptosis, the nuclear Wnt13C expression is regulated translationally; nuclear Wnt13 favors apoptosis through regulating the activity/expression of apoptosis-related factors; …

Insights Into Expression, Cellular Localization, And Regulation Of Supernatant Protein Factor, A Putative Regulator Of Cholesterol Biosynthesis, Elzbieta Ilona Stolarczyk

University of Kentucky Doctoral Dissertations

SPF (Supernatant Protein Factor) is a cytosolic protein that stimulates at least two enzymes in the cholesterol biosynthetic pathway: squalene monooxygenase and HMGCoA reductase. The mechanism of action has not been established but may be related to lipid transfer between intracellular membranes.

There are three human genes for SPF: SEC14L2 (SPF1), SEC14L3 (SPF2) and SEC14L4 (SPF3). The present study differentiates these closely related genes by evaluating their tissue-specific and relative expression levels. SPF1 mRNA was found to be most abundant in liver, mammary gland and stomach. SPF2 showed negligible expression in all tissues tested; SPF3 expression pattern was similar to …