Crystal structure of the ligand-free form of the Vps10 ectodomain of dimerized Sortilin at acidic pH
Yabe-Wada, T., Matsuba, S., Unno, M., Onai, N.(2018) FEBS Lett 592: 2647-2657
- PubMed: 29972886 
- DOI: https://doi.org/10.1002/1873-3468.13181
- Primary Citation of Related Structures:  
5ZNN - PubMed Abstract: 
Sortilin is a multifunctional sorting receptor involved in cytokine production in immune cells. To understand the mechanism of Sortilin-mediated cytokine trafficking, we determined the 2.45-Å structure of the dimerized Sortilin ectodomain (sSortilin or the Vps10-domain) crystallized at acidic pH. Substantial conformational changes upon dimerization lead to the intermolecular hydrophobic interaction between the conserved E455 and F137. Analysis of the electrostatic surface and size-exclusion chromatography revealed that sSortilin dimerization occurs due to an increase in hydrophobic interactions at the neutral dimer interface at acidic pH. The N682-attached N-glycan in the vicinity of the dimer interface implies its involvement in the dimerization. The disruption of Sortilin dimerization by mutations impairs efficient interferon-alpha secretion from cells. These results suggest the functional importance of Sortilin dimerization in cytokine trafficking.
Organizational Affiliation: 
Department of Immunology, Kanazawa Medical University, Uchinada, Japan.