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In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
Origin and function of ubiquitin-like proteins
1Yale University, Department of Molecular Biophysics & Biochemistry, 266 Whitney Avenue, PO Box 208114, New Haven, Connecticut 06520, USA. mark.hochstrasser@yale.edu
Nature
|March 28, 2009
Summary
Ubiquitin-like proteins (UBLs) modify eukaryotic proteins, controlling vital cellular processes. Evidence suggests UBL conjugation evolved before eukaryotes, originating from prokaryotic systems.
Area of Science:
- Molecular Biology
- Biochemistry
- Evolutionary Biology
Background:
- Eukaryotic proteins undergo modifications like ubiquitin and ubiquitin-like protein (UBL) conjugation.
- UBLs regulate crucial physiological processes, including protein interactions with the proteasome and chromatin recruitment.
- These modifications are often transient and mediated by specific enzyme systems.
Purpose of the Study:
- To explore the evolutionary origins of UBL-protein conjugation systems.
- To investigate the potential prokaryotic ancestry of UBL modification pathways.
- To determine if UBL conjugation predates the emergence of eukaryotes.
Main Methods:
- Comparative analysis of protein modification systems.
- Examination of enzyme families involved in UBL conjugation and deconjugation.
- Bioinformatic analysis of protein sequences and evolutionary relationships.
Main Results:
- UBL-protein modification is a widespread regulatory mechanism in eukaryotes.
- Evidence indicates a link between UBL systems and prokaryotic sulphurtransferase systems.
- Proteins homologous to UBL-conjugating and deconjugating enzymes were present in the last common ancestor of eukaryotes.
Conclusions:
- UBL-protein conjugation likely evolved from prokaryotic systems.
- The fundamental machinery for UBL conjugation predates eukaryotic evolution.
- UBL modification is an ancient biological process with deep evolutionary roots.
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