Fig. 2. Genetic epistatis assays reveal that Rhomboid-7 is an upstream regulator of the Pink1 pathway.

(A) Overexpression of rhomboid-7 causes a rough eye phenotype. Overexpression of both rhomboid-7 and pink1 enhances the rough eye (C), through an interaction that requires the catalytic serine of Rhomboid-7 (C). The rhomboid-7 phenotype is suppressed in pink1 mutants (D), whereas the pink1 phenotype is not suppressed in rhomboid-7 mutants (E). rhomboid-7 overexpression is also enhanced by co-expression with parkin (F) and omi (G). Synergistic interaction of Rhomboid-7 and Omi requires the catalytic serine of Rhomboid-7 (H). The rhomboid-7 phenotype is also suppressed by loss of parkin (I) and omi (J). (K) Mean + s.d. from more than 50 flies of specified genotypes, scored blind for relative roughness (see Methods).