α-SynD135 accumulates specifically in the central nervous system of symptomatic hA30P α-syn mice, regardless of parkin expression status. (A) Micrographs illustrating specific immunoreactivity in coronal brainstem sections from a representative symptomatic hA30Pα-syn mouse with functional parkin alleles, stained with anti-α-synD135 antibody before (left) and after absorption with recombinant α-synY133, full-length α-syn or α-synD135. Scale bars: 25 μm. (B) Comparative staining for α-synD135 in the brainstem of representative symptomatic and healthy hA30Pα-syn mice with functional parkin alleles; similar results were obtained in hA30Pα-syn mice with no functional parkin alleles. Scale bars: 100 μm. (C) Representative spectrum illustrating the detection, by MS, of the C-terminal fragment of full-length α-syn (mass/charge = 1441 with z = 3) and α-synD135 (mass/charge = 1243 with z = 3) in the SDS-soluble fraction of proteins from brain lysates from hA30Pα-syn+/+ mice; peptides (sequence indicated in blue) were fragmented and unambiguously identified by tandem MS.