New insights on the protein-ligand interaction differences between the two primary cellular retinol carriers.

ABSTRACT: The main retinol carriers in the cytosol are the cellular retinol-binding proteins types I and II (CRBP-I and CRBP-II), which exhibit distinct tissue distributions. They play different roles in the maintenance of vitamin A homeostasis and feature a 100-fold difference in retinol affinity whose origin has not been described in detail. NMR-based hydrogen/deuterium exchange measurements show that, while retinol binding endows both proteins with a more rigid structure, many amide protons exchange much faster in CRBP-II than in CRBP-I in both apo and holo form, despite the conserved three-dimensional fold. The remarkable difference in intrinsic stability between the two homologs appears to modulate their binding properties: the stronger retinol binder CRBP-I displays a reduced flexibility of th

SUBMITTER: Franzoni L 

PROVIDER: S-EPMC3035496 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature