How do chaperonins fold protein?
نویسنده
چکیده
Protein folding is a biological process that is essential for the proper functioning of proteins in all living organisms. In cells, many proteins require the assistance of molecular chaperones for their folding. Chaperonins belong to a class of molecular chaperones that have been extensively studied. However, the mechanism by which a chaperonin mediates the folding of proteins is still controversial. Denatured proteins are folded in the closed chaperonin cage, leading to the assumption that denatured proteins are completely encapsulated inside the chaperonin cage. In contrast to the assumption, we recently found that denatured protein interacts with hydrophobic residues at the subunit interfaces of the chaperonin, and partially protrude out of the cage. In this review, we will explain our recent results and introduce our model for the mechanism by which chaperonins accelerate protein folding, in view of recent findings.
منابع مشابه
Protein unfolding and folding by GroEL-GroES
Background: Chaperonins like the GroEL-GroES complex facilitate protein folding in the cell. Results: Substrate proteins are captured by the open, trans ring of the GroEL-ATP-GroES complex and are partially unfolded. Conclusion: Maximally efficient folding requires repeated cycles of substrate protein unfolding by the GroEL-GroES complex. Significance: Establishing how substrate proteins are pr...
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