Abstract
Phospholipase D1 (PLD1) and D2 (PLD2) are lipid metabolizing enzymes that produce phosphatidic acid and contribute to pathologies such as cancer, neurodegeneration, and cardiovascular diseases. Recently, the ARF-like GTPase 11 (ARL11) was identified as an activator of PLD1, but the mechanism of this stimulation remained unknown. Here, we use in vitro biochemical assays and structural predictions to determine that ARL11 interacts with PLD1 using three adjacent, biochemically distinct interfaces, and that the ends of PLD1’s disordered loop form ordered structures to facilitate these interactions. Both PLD1 and PLD2 are peripheral membrane proteins that have differing subcellular localization important for their regulation. At their N-termini are tandem phox homology (PX) and pleckstrin homology (PH) domains which facilitate membrane association, but their phospholipid iii binding specificity remains contested. Here, we present advancements towards the purification of the PLD1 and PLD2 tandem PXPH domains, and the elucidation of their lipid binding partners. The development of PLD1 and PLD2 inhibitors for pharmaceutical application has been pursued for decades, but there are currently no isoform-specific inhibitors approved for clinical use. Using anchor-and-grow starting from established PLD inhibitor backbones, and de novo synthesis of inhibitors, we present a series of potential PLD1 and PLD2 inhibitors scored according to their druglikeness and calculated binding affinity.
Year
2026
Document Type
Dissertation
Keywords
PLD, phospholipase D, ARL, ARF-like GTPase, Structure prediction, phox homology
Degree Name
Doctor of Philosophy (PhD)
Department
Biological Science
Advisor
Michael Airola
Recommended Citation
Marr, Douglas Jay, "Structural and Biochemical Insights Into Phospholipase D Function and its Small GTPase Stimulators" (2026). Electronic Dissertations and Theses, 2010-current. 172.
https://commons.library.stonybrook.edu/electronic-disserations-theses/172