Figure 3: Parkin sulfhydration at specific cysteine residues enhances its protective functions.

(a) Mass spectrometry detects parkin cysteines sulfhydrated by H₂S donor NaHS. (b) C59S, C95S and C182S mutations all substantially reduce parkin activity stimulation by H₂S in HEK293 cells. (c) Cell death as monitored by trypan blue exclusion assay in tet-repressible AIMP2-expressing PC12 cells is prevented by parkin overexpression and by GYY4137, whose protective effect is not evident in the absence of parkin, with parkin–C95S or with the T240R catalytically inactive parkin mutant. n=3–6 with *P<0.01 by one-way analysis of variance. All data expressed as mean±s.e.m.