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Growing up in a dangerous environment: a network of multiple targeting and folding pathways for nascent polypeptides

B Bukau1, T Hesterkamp, J Luirink

  • 1Zentrum für Molekulare Biologie, Universität Heidelberg, Germany. bukau@sun0.urz.uni-heidelberg.de

Trends in Cell Biology
|December 1, 1996
PubMed

Insights

Newly synthesized proteins face risks like aggregation. A cytosolic system of molecular chaperones and folding catalysts assists nascent polypeptides, promoting efficient protein folding and targeting through diverse pathways.

Area of Science:

  • Molecular biology
  • Cellular biology
  • Biochemistry

Background:

  • Nascent polypeptides emerging from the ribosome are vulnerable to aggregation.
  • Proteins destined for organelles require precise targeting and must avoid premature folding.

Purpose of the Study:

  • To review the interactions between the cytosolic system and nascent polypeptides.
  • To discuss new concepts for protein folding in the cytosol.

Main Methods:

  • Literature review focusing on molecular chaperones, folding catalysts, and targeting factors.
  • Analysis of new concepts in cytosolic protein folding and targeting.

Main Results:

  • The cytosolic system, comprising molecular chaperones, folding catalysts, and targeting factors, ensures high precision and speed in protein biogenesis.
  • A flexible network of multiple unassisted and assisted pathways promotes protein folding and targeting.

Conclusions:

  • Protein folding and targeting are complex processes requiring a sophisticated cytosolic system.
  • New concepts suggest a network of pathways facilitates efficient nascent polypeptide processing.

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