Figure 7. ATP13A1 prevents wasteful ERAD of mislocalized and misoriented proteins.
(A) Dislocation by ATP13A1 provides mislocalized mitochondrial TA proteins additional opportunities to insert into the outer membrane of mitochondria (mito.) and protects against SPP-mediated ERAD.
(B) Correct topogenesis of certain signal sequences and type II TMs requires ATP13A1, which prevents ERAD of misoriented substrates mediated by ER-resident ubiquitin ligases. Ribosomes present during cotranslational protein translocation and TM insertion are omitted for clarity.