Heat-shock protein HSP70 decreases activity of proteasomes in human neuroblastoma cells treated by amyloid-beta 1-42 with isomerized Asp7

Interplay between recombinant Hsp70 and proteasomes: proteasome activity modulation and ubiquitin-independent cleavage of Hsp70

“…Western blot with antibodies to the α-subunit of 11S regulator and αsubunits (1, 2, 3, 5, 6, 7 (∑α)) of the 20S proteasomes was performed not be repaired, it is delivered for degradation by UPS, chaperone-mediated autophagy (CMA), or macroautophagy depending on properties of the protein (Ciechanover and Kwon 2015). In the framework of PQC, Hsp70 is tightly linked with the UPS, and experimental evidences favor the intensive interplay and mutual effects of the UPS components and Hsp70 (Bobkova et al 2015;Grune et al 2011;Morozov 2017;Qian et al 2006;Yurinskaya et al 2015a). The deeper insight into the mechanisms of modulation of proteasomes by Hsp70 can help explain beneficial effects of Hsp70-based therapy on neurodegenerative diseases (Bobkova et al 2014;Kalmar et al 2012;Turturici et al 2011;Wang et al 2013), which are characterized by attenuated or compromised PQC and UPS (Bendotti et al 2012;Bentea et al 2016;Gestwicki and Garza 2012;Ross and Poirier 2004;Tseng et al 2008).…”

“…On the other hand following the stress relief, Hsp70 is itself ubiquitinated by co-chaperone CHIP and rapidly degraded in the 26S proteasome (Qian et al 2006;Soss et al 2015). Taken together, a growing body of evidence indicates that Hsp70 can influence activity, substrate specificity, and subunit composition of the intracellular proteasomes (Bobkova et al 2015;Grune et al 2011;Lyupina et al 2013;Morozov 2017).…”