Fig. 2

Prominent accumulation ofαSyn/phosphorylated αSyn (PαSyn) in the spinal cord of Pla2g6-knockout (KO) mice at the preclinical-stage. a, f wild-type mice; b-d, g-m, Pla2g6-KO mice at 15 weeks; e, Pla2g6-KO mice at 2 years; a-n, Anterior part of spinal cords; a-c, e, Immunohistochemistry for αSyn; d, Immunohistochemistry for αSyn plus Periodic Acid Shiff (PAS); f-n, Immunohistochemistry against PαSyn (f-h, j), CCO (i), and TOM20 (k), and cathepsin D (n), Immunohistochemistry for PαSyn (l) or KDEL (m) plus PAS, respectively; Scale bar represents 80 μm in (a, b, f, g), and 20 μm in (c-e, h-n). The graph shows the number of neurons filled with PαSyn-positive granules in wild-type mice at 2 years of and Pla2g6-KO mice at 15 weeks, 1 year, and 2 years of age. a The gray matter of the control spinal cord is moderately stained, showing a punctate pattern; b, c αSyn expression is highly diffuse in the gray matter of young Pla2g6-KO mice. The neuron is mildly positive for αSyn (arrow in c), which is filled with PAS-positive granules, as shown in a serial section (d). e In the gray matter of KO mice at end stage, several vacuoles and spheroids are seen, which are negative for αSyn (*). f No staining is seen in the control. (g) In KO mice at the pre-clinical stage, there are many tiny PαSyn-positive granules in the anterior horn cells (arrows) and the proximal axons (white arrowheads). h, i, PαSyn-positive small granules (arrows in h) are virtually negative for CCO (arrows in i) in the same neurons as in the serial section. j, k Very small PαSyn-positive granules (arrows in j) are prominently observed in the same neurons filled with TOM20-positive granules (arrows in k) in the serial section. l, m, PAS-positive granules are PαSyn-positive (l, arrows) and KDEL-negative (m, arrows). n A swollen neuron is negative for cathepsin D (arrow)