SOD1 and amyotrophic lateral sclerosis: A study demonstrated that misfolded proteins, such as huntington (Htt) in Huntington’s disease, superoxide dismutase 1 (SOD1) in ALS, and α-synuclein (a-syn) in Parkinson’s disease, were all shown to increase KDEL receptor expression, and the knock down of KDEL receptors led to increased levels of the disease-related proteins.