The Hsp70, HSPA1A, was used as the classic marker of stress-induced HSP expression in the following experimental paradigms in dissociated cultures of murine spinal cord-DRG: Constitutive induction of Hsp70 by an HSP90 inhibitor, thermal stress, and expression of mutant proteins (SOD1 and FUS) responsible for familial forms of ALS as models of proteotoxic stress linked to neurodegenerative disease. Here, SOD1 is linked to amyotrophic lateral sclerosis.