Protease-activated alpha-2-macroglobulin can inhibit amyloid formation via two distinct mechanisms.

ABSTRACT: ?(2)-Macroglobulin (?(2)M) is an extracellular chaperone that inhibits amorphous and fibrillar protein aggregation. The reaction of ?(2)M with proteases results in an 'activated' conformation, where the proteases become covalently-linked within the interior of a cage-like structure formed by ?(2)M. This study investigates, the effect of activation on the ability of ?(2)M to inhibit amyloid formation by A?(1-42) and I59T human lysozyme and shows that protease-activated ?(2)M can act via two distinct mechanisms: (i) by trapping proteases that remain able to degrade polypeptide chains and (ii) by a chaperone action that prevents misfolded clients from continuing along the amyloid forming pathway.

SUBMITTER: Wyatt AR 

PROVIDER: S-EPMC3581772 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature