East Carolina University : Research and Creative Achievement Week 2011
determine the magnitude of the change in EphA6 protein expression in WT versus EphA2 knockout mice as well as the localization of EphA6 protein to gain insight into what cell types may be influenced. This information will help us understand the potential reciprocal interactions between EphA2 and EphA6 and their role in modulating myocardial injury. Additionally, long term studies are in progress to investigate the effects of EphA2 deletion on myocyte hypertrophy, interstitial fibrosis, blood pressure, and cardiac function. The Effects of PFOA on TIAR vs. TDAR & PPAR-± Activity, John Creech, Jamie DeWeitt, Department of Chemistry, East Carolina University, Greenville, NC 27858 Perfluorooctanoic acid (PFOA) is an environmental pollutant and xenobiotic that has been demonstrated to be carcinogenic, developmentally toxic, bioaccumulative and to have antiinflammatory properties through experiments in mouse models. PFOA typically reduces relative spleen and thymus size while increasing the size of the liver. The peroxisome proliferator-activated receptor- ± (PPAR-±) is activated by PFOA and regulates genes associated with glucose and lipid homeostasis, cell proliferation and cell differentiation within cells expressing the PPAR-± isotype. The thymus is a major site of T-cell proliferation and differentiation, therefore thymus protein extracts were tested for the presence of PPAR-±. PFOA inhibits the release of signaling cues from Tcells, such as interleukins, which activate B-cells to release primary antibodies (IgM) to antigens present within the blood, a process which is the T-cell dependent antibody response (TDAR). This study investigated the T-cell independent antibody response (TIAR) induced by a T-independent (TI) antigen, DNP-Ficoll, in C57Bl/6 mice exposed to PFOA. Mice were exposed to PFOA for a total of 15 days via drinking water at doses of 0, 0.94, 1.88, 3.75 and 7.5 mg PFOA/ kg body weight (BW). The relative weights of spleens from mice that received 3.75 & 7.5 mg/kg doses were reduced in comparison with control mice that received a 0 mg/kg dose. There was an observed dose-dependent exponential increase in the absolute weights of mouse livers relative to control mice. DNP-Ficollspecific IgM titers were reduced in mice that received 1.88, 3.75 & 7.5 mg PFOA/ kg BW doses, indicating that PFOA suppressed the TIAR to TI antigens. In conclusion, suppression of the TIAR may be a more sensitive indicator of immunosuppression than the TDAR.
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Characterization of DNA Polymerase Delta using a combined in vivo and in vitro strategy, Lena Keller , Chad Hunter, Bonnie Bolkna, Tim Christensen, Department of Biology, East Carolina University, Greenville, NC 27858 Cancer can be caused by defects in the regulation of DNA replication. Abnormal DNA replication can lead to unregulated growth, failure to differentiate, and aberrations in chromosome biology. Numerous different proteins are involved in DNA replication and understanding the role of these proteins is essential in understanding the nature of cancer. Of these different proteins involved in DNA replication, one of the most important is DNA Polymerase Delta (´). DNA Polymerase ´ is involved in elongation of the lagging strand of DNA during the S phase of the cell cycle. 203
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