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Updated: Mar 14, 2026
06:58
Global Identification of Co-Translational Interaction Networks by Selective Ribosome Profiling
Published on: October 7, 2021
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Exploring the capacity of trigger factor to function as a shield for ribosome bound polypeptide chains.
Sladjana Tomic1, Arthur E Johnson, F Ulrich Hartl
1Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany.
FEBS Letters
|December 20, 2005
Summary
Trigger factor (TF) chaperone protects nascent polypeptides from degradation. This protection is not universal but depends on hydrophobic interactions with the polypeptide chain, not just proximity.
Area of Science:
- Bacteriology
- Molecular Biology
- Protein Folding
Background:
- Ribosome-bound trigger factor (TF) is the initial chaperone for nascent polypeptide chains in bacteria.
- TF is hypothesized to shield short nascent chains (approx. 130 residues) in a protective cradle.
Purpose of the Study:
- To investigate the protective capacity of TF against protease digestion for longer nascent chains.
- To determine if TF acts as a general shield for all nascent polypeptides.
Main Methods:
- Assessing protease K digestion of nascent luciferase and alpha-synuclein chains in the presence of TF.
- Utilizing crosslinking to determine proximity of nascent chains to TF.
Main Results:
- Nascent luciferase chains up to 280 residues showed relative protection from proteinase K digestion by TF.
- Nascent alpha-synuclein chains, despite proximity to TF, were not protected.
- Protease protection by TF correlated with hydrophobic interactions with the nascent polypeptide.
Conclusions:
- TF does not function as a general shield for all nascent polypeptide chains.
- TF-mediated protease protection is sequence- and interaction-dependent, relying on hydrophobic contacts.
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