CALR and proximal spinal muscular atrophy: Using quantitative western blot and immunohistochemistry, we demonstrated for the first time that calreticulin is reduced in expression in spinal cords from late-symptomatic SMA mice, and in agreement with proteomic studies of other ALS cells and tissue [44,48,50], we measured increased levels of calreticulin in spinal cord extracts from symptomatic ALS SOD1G93A mice.