Physical Sciences and Mathematics Commons^™

Slc30a3 (Znt3) Oligomerization By Dityrosine Bonds Regulates Its Subcellular Localization And Metal Transport Capacity, Gloria Salazar, Juan M. Falcon-Perez, Robert W. Harrison, Victor Faundez

Computer Science Faculty Publications

Non-covalent and covalent homo-oligomerization of membrane proteins regulates their subcellular localization and function. Here, we described a novel oligomerization mechanism affecting solute carrier family 30 member 3/zinc transporter 3 (SLC30A3/ZnT3). Oligomerization was mediated by intermolecular covalent dityrosine bonds. Using mutagenized ZnT3 expressed in PC12 cells, we identified two critical tyrosine residues necessary for dityrosine-mediated ZnT3 oligomerization. ZnT3 carrying the Y372F mutation prevented ZnT3 oligomerization, decreased ZnT3 targeting to synaptic-like microvesicles (SLMVs), and decreased resistance to zinc toxicity. Strikingly, ZnT3 harboring the Y357F mutation behaved as a ‘‘gain-of-function’’ mutant as it displayed increased ZnT3 oligomerization, targeting to SLMVs, and increased resistance …