Sean Henley

Development of structure/property relationships for new adhesive interlayers used in inkjet packaging applications. Including formulation, coating and physical characterization of materials and adhesive performance. Supporting the current production of an optical film used in printing and characterizing the drying process for a new coating solvent.

Assisted with experiments, and collection of data for publication.

purification of the full length NCOA4 protein, role of ferritinophagy in iron homeostasis, NCOA4 FL binding to ferritin to facilitate ferritinophagy.

Ferritin safeguards cells from iron-induced oxidative stress by oxidizing and storing Fe2+ within its nanocage, yet how its macromolecular architecture enables responsiveness to the cellular chemical environment remains unclear. Here, we show that ferritin's iron-oxidation activity is modulated by an electrostatic gating mechanism centered at its 3-fold channels and sensitive to solution charge conditions representative of intracellular metabolites. At physiologically relevant nucleotide concentrations, ferritin-catalyzed Fe2+ oxidation is strongly attenuated in the presence of triphosphate nucleotides, while diphosphates and monophosphates exert progressively weaker effects, indicating that ferritin responds selectively to the charge density and geometry of the phosphate chain, rather than nucleotide identity. High-resolution cryo-electron microscopy identifies condition-dependent differences in non-protein density within and near the ferritin 3-fold channels, consistent with changes in the local solvent and/or ion environment, rather than discrete ligand binding. Fluorescence and calorimetric measurements reveal weak, reversible nucleotide association (KD ∼ 1 mM), supporting a low-affinity, dynamic electrostatic interaction mode. The inhibitory trend persists under reduced oxygen conditions and across ferritin assemblies with varying H/L composition, supporting physiological relevance across cellular oxygen tensions and native ferritin heteropolymers. Ferritin activity is similarly modulated in bacterial, yeast, and human cell lysates under near-physiological conditions, demonstrating the robustness of this behavior in complex environments. Together, these findings establish ferritin as a biological macromolecule whose intrinsic channel electrostatics enable reversible modulation of iron uptake and oxidation in response to its chemical environment.