α-Synuclein has structural and functional similarities to small heat shock proteins

Protein phosphatase inhibitor-1 (PPI-1) has protective activities in stress conditions in E. coli

“…4D). These results suggest that the Nterminal regions of PPI-1 (especially a.a. [6][7][8][9][10][11][12][13][14][15][16] are crucial for the protection of cells from heat stress.…”

“…Because proteins with unfolded native conformations are increasingly implicated in the regulation of many functions in the cell [13,15], we investigated whether PPI-1 functions in protein-protein interactions. Interestingly, protein turbidity assays showed that PPI-1 had nonspecific interactions with E. coli cellular proteins and prevented their aggregation under thermal stress in vitro ( Fig.…”

Cyclization of α-Synuclein Derived Peptide Increases Its Chaperone-Like Activity

“…The capacity of peptides to suppress heat-induced aggregation of ADH was determined according to the method described earlier [4]. Briefly, a known amount of peptide (50 *Address correspondence to this author at the Department of Biological and Molecular Engineering, College of Engineering, Ajou University, Suwon, South Korea; Fax: 82-31-219-2394; E-mail:doohunkim@ajou.ac.kr µg or 100 µg of ADH) was denatured in 50mM phosphate buffer, pH 7.0, containing 0.1 M NaCl at 48 °C.…”

“…Like small heat shock proteins(sHSPs), α-synuclein exhibits chaperonelike activity by suppressing protein aggregation under denaturing conditions and, in some instances, protects the biological activity of several enzymes as well [4]. Therefore, α-synuclein should be able to suppress aggregations of model substrate proteins during thermal-and chemical-stresses in an ATP-independent manner [4][5][6].…”

“…α-Synuclein, a major component of Lewy Bodies (LB), has been shown to protect a wide variety of proteins from aggregation under denaturing conditions [1][2][3][4]. Like small heat shock proteins(sHSPs), α-synuclein exhibits chaperonelike activity by suppressing protein aggregation under denaturing conditions and, in some instances, protects the biological activity of several enzymes as well [4].…”