Molecular Chaperones in the Cytosol: from Nascent Chain to Folded Protein

@article{Hartl2002MolecularCI,
  title={Molecular Chaperones in the Cytosol: from Nascent Chain to Folded Protein},
  author={F. Ulrich Hartl and Manajit Hayer‐Hartl},
  journal={Science},
  year={2002},
  volume={295},
  pages={1852 - 1858}
}
Efficient folding of many newly synthesized proteins depends on assistance from molecular chaperones, which serve to prevent protein misfolding and aggregation in the crowded environment of the cell. Nascent chain–binding chaperones, including trigger factor, Hsp70, and prefoldin, stabilize elongating chains on ribosomes in a nonaggregated state. Folding in the cytosol is achieved either on controlled chain release from these factors or after transfer of newly synthesized proteins to downstream… 
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Chaperone-Assisted Folding of Newly Synthesized Proteins in the Cytosol

Recent advances have determined the atomic structure of the Trigger Factor, providing new, exciting insights into the role of ribosome-associated chaperones in co-translational protein folding.

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This review focuses on recent advances in understanding the mechanisms of chaperone action in promoting and regulating protein folding and on the pathological consequences of protein misfolding and aggregation.

Functions of Ribosome-Associated Chaperones and their Interaction Network

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Molecular chaperones prevent the potentially toxic aggregation of newly synthesised polypeptides during translation and when mature proteins unfold during stress conditions or ageing.

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This work focuses on the molecular mechanisms by which heat‐shock protein 70 (Hsp70), Hsp100 and small Hsp chaperones liberate and refold polypeptides trapped in protein aggregates.

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Structural insights into Trigger Factor reveal an intricate cradle-like structure that, together with the exit site of the ribosome, forms a protected environment for the folding of newly synthesized proteins.

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Cofactors and co-chaperones of the chaperonin CCT: mechanistic insights and in vivo relevance

The role of C'C'T co-chaperones (PFD) and cofactors (PhLP) in modulating the chaperonin's function is illuminated and new research prospects are opened up by identifying novel genetic interactors of CCT.
...

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