Figure 7

The Oxidoreductase and Chaperone Activities of PDI Are Protective against Mutant TDP-43 Induced Cell Death

(A) Cells expressing EGFP (row 1), TDP-WT (row 2) or TDP-M337V (row 3), co-expressing PDI-WT or PDI-QUAD or BMC treated (rows 4, 5, 6), arrows represent apoptotic nuclei.

(B) Over-expression of PDI-WT, PDI-QUAD, or BMC treatment with TDP-M337V resulted in significantly fewer cells with apoptotic nuclei compared with cells transfected with empty vector (∗p < 0.05). A significant difference was observed between TDP-WT and TDP-M337V expressing cells (∗∗p<0.01).

(C) Immunocytochemistry using activated caspase-3 antibodies (red). Cells expressing TDP-WT (row 1) or TDP-M337V (row 2, arrows representing caspase-3 activation), co-expressing PDI-WT or PDI-QUAD, or treated with BMC (rows 3, 4, 5).

(D) Over-expression of PDI-WT (∗∗∗p < 0.001), PDI-QUAD or treatment with BMC (∗∗p < 0.01), significantly decreased the proportion of cells with activated caspase-3.

(E) Immunocytochemistry using anti-activated Bax antibodies (red). Cells expressing pEGFP (row 1), TDP-WT (row 2), or TDP-M337V (row 3, arrows representing Bax activation), co-expressing PDI-WT or PDI-QUAD, or treated with BMC (rows 4, 5, 6).

(F) Over-expression of either PDI-WT or PDI-QUAD (∗p < 0.05), or treatment with BMC (∗∗p < 0.01), significantly decreased the proportion of cells with activated Bax compared with cells expressing empty vector.

(G) Primary neurons expressing EGFP (row 1), TDP-WT (row 2) or TDP-M337V (row 3), co-expressing PDI-WT, PDI-QUAD, or treated with BMC (rows 4, 5, 6), arrows represent apoptotic nuclei.

(H) Mutant TDP-M337V expression induced apoptosis (∗∗∗p < 0.001); however, over-expression of PDI-WT (∗∗∗p < 0.001), PDI-QUAD (∗p < 0.05) or administration of BMC (∗∗p < 0.01) resulted in significantly fewer neurons undergoing apoptosis.

Scale bars: 8 μm in (A), (G), 10 μm in (C), 4 μm in (E).