Varied effects of Pyrococcus furiosus prefoldin and P. furiosus chaperonin on the refolding reactions of substrate proteins.
Prefoldin is a molecular chaperone found in the archaeal and eukaryotic cytosol. Prefoldin can stabilize tentatively nascent polypeptide chains or non-native forms of mainly cytoskeletal proteins, which are subsequently delivered to group II chaperonin to accomplish their precise folding. However, the detailed mechanism is not well known, especially with regard to endogenous substrate proteins. Here, we report the effects of Pyrococcus furiosus prefoldin (PfuPFD) on the refolding reactions of Pyrococcus furiosus citrate synthase (PfuCS) and Aequorea enhanced green fluorescence protein (GFPuv) in the presence or absence of Pyrococcus furiosus chaperonin (PfuCPN). We confirmed that both PfuPFD and PfuCPN interacted with PfuCS and GFPuv refolding intermediates. However, the interactions between chaperone and substrate were different for each case, as was the final effect on the refolding reaction. Effects on the refolding reaction varied from passive effects such as ATP-dependent binding and release (PfuCPN towards GFPuv) and binding which leads to folding arrest (PfuPFD towards GFPuv), to active effects such as net increase in thermal stability (PfuCPN towards PfuCS) to an active improvement in refolding yield (PfuPFD towards PfuCS). We postulate that differences in molecular interactions between substrate and chaperone lead to these differences in chaperoning effects.
Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Tottori 680-8552, Japan.
Kunihiro
K
Hongo
Hiroshi
H
Itai
Tomohiro
T
Mizobata
Yasushi
Y
Kawata
D000255:Adenosine Triphosphate / Q000737:chemistry; D019843:Archaeal Proteins / Q000737:chemistry* / Q000302:isolation & purification; D018833:Chaperonins / Q000737:chemistry* / Q000302:isolation & purification; D002950:Citrate (si)-Synthase / Q000737:chemistry; D003035:Cobalt / Q000737:chemistry; D049452:Green Fluorescent Proteins / Q000737:chemistry; D007700:Kinetics; D008274:Magnesium / Q000737:chemistry; D018832:Molecular Chaperones / Q000737:chemistry* / Q000302:isolation & purification; D058849:Protein Refolding; D020027:Pyrococcus furiosus
D019843:Archaeal Proteins; D018832:Molecular Chaperones; C112806:prefoldin; D049452:Green Fluorescent Proteins; D003035:Cobalt; D000255:Adenosine Triphosphate; D002950:Citrate (si)-Synthase; D018833:Chaperonins; D008274:Magnesium