Heat shock cognate 71 kDa protein (HSPA8) translocates substrates from the cytosol to the lysosomal membrane. Subsequently, the substrate unfolds and binds to HSPA8 in the lysosomal lumen. HSPA8 facilitates the transport of the unfolded substrate to the lumen where it is then degraded (Agarraberes FA et al. 1997, Cuervo AM et al. 1997).