CURF 1: Lipid Kinases and Plasma Membrane Localization

Hello! My name is Max Ehrlich, and I am a sophomore majoring in History and Molecular Biology with a minor in Chemistry and a certificate in Conceptual Foundations of Medicine. I will be conducting my Chancellor’s Undergraduate Research Fellowship at the Hammond lab in the University of Pittsburgh Department of Cell Biology, under my mentor Dr. Gerry Hammond and a graduate student, Claire Weckerly. A fun fact about me is that I love to read, especially books about the Cold War time period!

I first got interested in research during high school when I was able to attend a weekly lecture series sponsored by the National Institutes of Health. Professors from nearby universities like Georgetown and George Washington as well as scientists from the FDA and NIH came and talked about their research-how it started, what they have learned, and where their project is going. Scientists presented everything from sea urchin immunology to a genetic approach for treating cystic fibrosis. Hearing these scientists talk so passionately about their projects made me want to conduct research as soon as I possibly could.

This semester, I will be researching the requirements for the enzyme PIP5K to localize at the cell membrane. PIP5K adds a phosphate to transform PI4P into PI(4,5)P2, a ubiquitous secondary messenger. Best known as PIP2, it is a phospholipid present in a majority of cells and deals with signaling in relation to other intracellular phospholipids, mostly with those on and around the plasma membrane. I will be testing how different amounts of phospholipids such as phosphatidic acid (PA), PI4P, PIP2, as well as several minor ones affect how PIP5K adheres to the plasma membrane instead of remaining cytosolic. Most experiments will consist of knockouts and knock-ins, where a certain enzyme will be turned off or an isoform introduced that will make significantly more product than is required by the cell. Each phospholipid will also have a biosensor with affinity to it introduced to the system. Biosensors, when hit with a laser during experiments, emit visible light, which can then be quantified with software. Since cells are miniscule, biosensors allow us to see what is going on within the cell and plasma membrane. This system allows me to manipulate the conditions inside the cell, determine where major phospholipids are, and where PIP5K is. I have started experimenting, and am excited to share preliminary results in my second update. An imbalance of several of these phospholipids is known to result in hypertrophic cardiomyopathy, or HCM. Understanding these phosphoinositide pathways will help understand how HCM occurs and how we can best approach treatments.

This is a graph of biosensor responses for a test experiment I recently ran. Both dishes received Carbachol (CCH), turning on PA production, after 2 minutes. After another 2 minutes, the control dish received CHIM, which should have no effect, while the test dish received Atropine, turning off PA production. PA concentration can be seen via the Nir1 biosensor, while the C1ab biosensor has affinity for diacylglycerol-the next product of the PA pathway.

My professional goals are currently to go to medical school or attend graduate school for the health sciences. Although I am not sure what I want to do yet, I know that I enjoy wet lab research and hope to continue to investigate the mysteries of lipids no matter what I end up doing.

Myself in the Hammond Lab!

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