Kristin Noell

Participant: PROMISE AGEP Research Symposium

Kristin Noell

Department: Natural Science

Institution: University of Maryland Eastern Shore (UMES)

 

ABSTRACT

Parasites as an Alternative Model for Lipid Metabolism: Gene Expression Analysis of an Oyster Parasite Perkinsus marinus during Lipid Starvation.

 

Our laboratory is interested in understanding the regulation of fatty acid biosynthesis in Perkinsus marinus. Previous work has shown that this parasite is capable of synthesizing its own fatty acids, a property that is unique among parasites that usually require the acquisition of certain essential fatty acids from their host. Fatty acid synthesis occurs in the cytosol from Acetyl CoA, which is derived from carbohydrate metabolism via citrate. In the cytosol, citrate can be cleaved into oxaloacetate and Acetyl CoA, or be converted to isocitrate by cytosolic aconitase. We are investigating the role of cytosolic aconitase as a potential branch point in this process, as we have evidence for phosphorylation of this enzyme in favoring citrate production. No one to our knowledge has delineated the role of cytosolic aconitase in fatty acid biosynthesis. We have performed differential mRNA gene expression in P. marinus, in which cells were starved of lipids for 11 days, as compared to lipid replete cells. Our results show that cytosolic aconitase was not differentially regulated at the level of mRNA expression, although citrate synthase was upregulated by approximately 3-fold. In addition, acetyl CoA carboxylase-2 (ACC-1) was down regulated 2 fold, although ACC-1 (which catalyzes the committed step of fatty acid synthesis) remained unchanged. This data indicates that both fatty acid synthesis and beta-oxidation are operating simultaneously during lipid starvation. Future work will explore the hypothesis that fatty acid synthesis for membrane production relies on de novo synthesis, whereas that present in lipid droplets is used for the TCA cycle. This and other aspects of lipid metabolism will be explored.

 

BIOGRAPHICAL SKETCH

Kristin Noell received her Bachelor’s in Forensic Science with a concentration in Biology from Fayetteville State University in 2010. Upon completion of her undergraduate degree, Kristin was award a Title III HBCU Master’s in STEM Scholarship to pursue her Master’s in Biology at Fayetteville State Univerity, in which her research focused on perfluroinated compounds and biochemical disruptions in zebrafish spp., her Master’s In Biology was awarded to her in 2012. Kristin is currently pursing her PhD in Toxicology at the University of Maryland Eastern Shore. She pursing her degree under the direction of Dr. Joseph S. Pitula, in which she is exploring cytosolic aconitase and involvement in lipid metabolism in a non- mammalian system, Perkinsus marinus. Kristin in currently in her 5^th year of her PhD and anticipates graduation by December 2017. She has presented her findings at several aquatic conferences, and plans to present her findings at the Society of Toxicology Meeting in March 2017.

 

GENERAL SUMMARY OF GRADUATE RESEARCH

 

 

SELECTED LIST OF PRESENTATIONS AND PUBLICATIONS

1. Ocean Science Meeting. American Society of Limnology and Oceanography. “Gene Expression analysis of a critical enzyme in Intermediary Metabolism in Perkinsus marinus”. Poster. New Orleans, LA. February, 2016.
2. Graduate Research Symposium. University Of Maryland Eastern Shore. “Evaluation of the Enzyme Aconitase in Regulating the Metabolic Response of an Oyster Pathogen Perkinsus marinus.” Poster. Princess Anne, MD. 2014-2016.
3. Aquatic Science Meeting. American Society of Limnology and Oceanography. “Evaluation of the Enzyme Aconitase in Regulating the Metabolic Responses of an Oyster Pathogen, Perkinsus marinus.” New Orleans, LA. 2013.