Wilson transporter ATP7B: Interactions, Lipids, Structure and RegulatiON

Descripción del proyecto

Comprender la regulación de ATP7B en la enfermedad de Wilson

El cobre es un micronutriente esencial para la salud, pero tanto su carencia como su exceso pueden resultar perjudiciales. La enfermedad de Wilson es un trastorno poco frecuente pero grave del metabolismo del cobre, causado por mutaciones en el gen ATP7B, que codifica una adenosina trifosfatasa encargada del transporte de este metal. Los tratamientos disponibles presentan diversas limitaciones, entre ellas la aparición de efectos secundarios. En el proyecto WILSON, que cuenta con el respaldo de las acciones Marie Skłodowska-Curie, se investigará la regulación de ATP7B en función de su estructura, entorno lipídico, proteínas asociadas y variantes genéticas. El objetivo es caracterizar la actividad ATPasa dependiente del cobre y analizar las mutaciones asociadas a la enfermedad de Wilson. Se expresará la proteína ATP7B humana completa en las líneas celulares HEK293 y HepG2 y se estudiará mediante ensayos funcionales y microscopía crioelectrónica. El proyecto contribuirá al desarrollo de terapias dirigidas y mejorará la comprensión del transporte de metales.

Objetivo

ATP7B is a copper-transporting ATPase responsible for secreting and regulating copper within the cell. Precise control is critical, as copper is an essential but potentially toxic element. Mutations in ATP7B cause Wilson disease, a rare but severe disorder caused by excess copper accumulation in several organs of the human body. Despite being a monogenic disease, current treatments are indirect and carry major side effects. The molecular-level regulation of ATP7B is still not completely understood. ATP7B has been associated with cancer resistance and neurodegenerative disorders indicating its broader biological relevance.
The WILSON project (Wilson transporter ATP7B: Interactions, Lipids, Structure and RegulatiON) will uncover how ATP7B is regulated by its N-terminal metal binding domains, C-terminal tail, lipid environment and protein partners, and how disease causing and common benign variants affect its function. The project proposes 6 objectives: define the requirements for copper-dependent ATPase activity; determine the effect of lipid composition; assess the role of copper chaperones; clarify the regulatory contributions of the N- and C-terminal regions; analyse how the effect of ATP7B's partners are altered in Wilson disease mutations; investigate the structural and functional effect of common SNPs.
To achieve these aims, full-length human ATP7B will be expressed in stable HEK293 and HepG2 cell lines, purified and reconstituted into lipid nanodiscs. Functional assays and single-particle cryo-EM will be combined with cellular imaging, fluorescent sensor-based cellular assays, and mass spectrometry based interactomics.
WILSON will deliver mechanistic insights into ATP7B regulation and disease variants, structural models including previously unresolved regions, and experimental platforms relevant for future studies. The findings will aid mutation-specific therapies for Wilson disease and broaden our knowledge of metal transport and metabolism.