Intricate mechanism (s) of substrate specificity and loss of function on disease mutation (K211N) of Parkin

Abstract

AbstractParkin mutations lead to the early onset of Parkinson’s disease. PINK1-mediated phosphorylation of its substrates Ubiquitin (Ub)-like proteins (NEDD8, Ubiquitin) and Ubiquitin-like (Ubl) domain activate autoinhibited Parkin. Substrate specificity on Parkin and the cause of loss of function in disease mutation K211N remain elusive. Herein, we determine the first crystal structure of human Parkin bound with phospho(p)-NEDD8 and establish the mechanism of substrate specificity on Parkin. RING0 pocket is specific for pUbl and does not bind with pUb/pNEDD8. In contrast, pNEDD8 has evolved to bind robustly in the RING1 pocket and shows higher activation of Parkin compared to pUb. Also, the binding of activators in the RING1 and RING0 pockets of Parkin leads to a distinct extent of RING2 displacement during Parkin activation. Furthermore, the crystal structure of pNEDD8-bound Parkin K211N reveals novel conformational changes due to N211 that lock RING2 with RING0 to inhibit Parkin activity without losing pNEDD8/pUb binding. This study would help design small-molecule Parkin activators against Parkinson’s disease.