Intriguingly, the over-expression of α-synuclein, a culprit protein in PD, protects DNAJC5/CSPα-deficient mice from neurodegeneration (Chandra et al., 2005), which suggests that α-synuclein may compensate for the loss of DNAJC5/CSPα in the nervous system. Here, DNAJC5 is linked to Parkinson disease.