Recombinant ATPases of the yeast 26S proteasome activate protein degradation by the 20S proteasome

• Published in: FEBS letters 2004-05, Vol.565 (1), p.39-42
• Main Authors: Takeuchi, Junko, Tamura, Tomohiro
• Format: Article
• Language: English
• Subjects: 26S proteasome; AAA-ATPase; Adenosine Triphosphatases - chemistry; Adenosine Triphosphatases - physiology; Adenosine Triphosphate - chemistry; Catalysis; Cysteine Endopeptidases - chemistry; DNA-Binding Proteins - physiology; Dose-Response Relationship, Drug; Electrophoresis, Polyacrylamide Gel; Endopeptidases - chemistry; Endopeptidases - physiology; Escherichia coli; Escherichia coli - metabolism; Hydrolysis; Multienzyme Complexes - chemistry; Peptide Hydrolases - chemistry; Plasmids - metabolism; Proteasome Endopeptidase Complex; Protein Folding; Protein Transport; Recombinant Proteins - chemistry; Saccharomyces cerevisiae; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - physiology; Schizosaccharomyces pombe Proteins - physiology; Time Factors
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/j.febslet.2004.03.073

The 26S proteasome contains a proteolytic core, 20S proteasome, and its regulatory particle, 19S complex. That regulatory particle contains six ATPases that are involved in unfolding and translocation of substrates to the 20S proteasome's catalytic chamber. We expressed ATPase-encoding genes of the regulatory particle of Saccharomyces cerevisiae and found that some recombinant ATPases can self-assemble into a high-molecular-weight protein complex in Escherichia coli. Purification of the Rpt1Rpt2 hetero-complex and the Rpt4 homo-complex for functional characterization demonstrated their contribution to energy-dependent protein degradation. Our finding, production of a functional subunit of the 19S regulatory particle in bacteria, is a simpler and technically advanced system to functionally characterize individual subunits.