TY - JOUR
T1 - Sequential mechanism of solubilization and refolding of stable protein aggregates by a bichaperone network
AU - Goloubinoff, Pierre
AU - Mogk, Axel
AU - Ben Zvi, Anat Peres
AU - Tomoyasu, Toshifumi
AU - Bukau, Bernd
PY - 1999/11/23
Y1 - 1999/11/23
N2 - A major activity of molecular chaperones is to prevent aggregation and refold misfolded proteins. However, when allowed to form, protein aggregates are refolded poorly by most chaperones. We show here that the sequential action of two Escherichia coli chaperone systems, CIpB and DnaK-DnaJ-GrpE, can efficiently solubilize excess amounts of protein aggregates and refold them into active proteins. Measurements of aggregate turbidity, Congo red, and 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid binding, and of the disaggregation/refolding kinetics by using a specific CIpB inhibitor, suggest a mechanism where (i) CIpB directly binds protein aggregates, ATP induces structural changes in CIpB, which (ii) increase hydrophobic exposure of the aggregates and (iii) allow DnaK-DnaJ-GrpE to bind and mediate dissociation and refolding of solubilized polypeptides into native proteins. This efficient mechanism, whereby chaperones can catalytically solubilize and refold a wide variety of large and stable protein aggregates, is a major addition to the molecular arsenal of the cell to cope with protein damage induced by stress or pathological states.
AB - A major activity of molecular chaperones is to prevent aggregation and refold misfolded proteins. However, when allowed to form, protein aggregates are refolded poorly by most chaperones. We show here that the sequential action of two Escherichia coli chaperone systems, CIpB and DnaK-DnaJ-GrpE, can efficiently solubilize excess amounts of protein aggregates and refold them into active proteins. Measurements of aggregate turbidity, Congo red, and 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid binding, and of the disaggregation/refolding kinetics by using a specific CIpB inhibitor, suggest a mechanism where (i) CIpB directly binds protein aggregates, ATP induces structural changes in CIpB, which (ii) increase hydrophobic exposure of the aggregates and (iii) allow DnaK-DnaJ-GrpE to bind and mediate dissociation and refolding of solubilized polypeptides into native proteins. This efficient mechanism, whereby chaperones can catalytically solubilize and refold a wide variety of large and stable protein aggregates, is a major addition to the molecular arsenal of the cell to cope with protein damage induced by stress or pathological states.
KW - CIpB
KW - Congo red
KW - DnaK
KW - Hsp104
KW - Protein disaggregation
UR - http://www.scopus.com/inward/record.url?scp=0033598703&partnerID=8YFLogxK
U2 - 10.1073/pnas.96.24.13732
DO - 10.1073/pnas.96.24.13732
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C2 - 10570141
AN - SCOPUS:0033598703
SN - 0027-8424
VL - 96
SP - 13732
EP - 13737
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 24
ER -