Cited by 77Heat shock proteins researchPhotosynthetic Processes and MechanismsUbiquitin and proteasome pathways

Structure, function, and substrates of Clp AAA+ protease systems in cyanobacteria, plastids, and apicoplasts: A comparative analysis

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Bouchnak, Imen, van Wijk, Klaas J.·2021·Journal of Biological Chemistry

Abstract

ATPases Associated with diverse cellular Activities (AAA+) are a superfamily of proteins that typically assemble into hexameric rings. These proteins contain AAA+ domains with two canonical motifs (Walker A and B) that bind and hydrolyze ATP, allowing them to perform a wide variety of different functions. For example, AAA+ proteins play a prominent role in cellular proteostasis by controlling biogenesis, folding, trafficking, and degradation of proteins present within the cell. Several central proteolytic systems (e.g., Clp, Deg, FtsH, Lon, 26S proteasome) use AAA+ domains or AAA+ proteins to unfold protein substrates (using energy from ATP hydrolysis) to make them accessible for degradation. This allows AAA+ protease systems to degrade aggregates and large proteins, as well as smaller proteins, and feed them as linearized molecules into a protease chamber. This review provides an up-to-date and a comparative overview of the essential Clp AAA+ protease systems in Cyanobacteria (e.g., Synechocystis spp), plastids of photosynthetic eukaryotes (e.g., Arabidopsis, Chlamydomonas), and apicoplasts in the nonphotosynthetic apicomplexan pathogen Plasmodium falciparum. Recent progress and breakthroughs in identifying Clp protease structures, substrates, substrate adaptors (e.g., NblA/B, ClpS, ClpF), and degrons are highlighted. We comment on the physiological importance of Clp activity, including plastid biogenesis, proteostasis, the chloroplast Protein Unfolding Response, and metabolism, across these diverse lineages. Outstanding questions as well as research opportunities and priorities to better understand the essential role of Clp systems in cellular proteostasis are discussed.

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  • In cyanobacteria, proteostasis is strongly influenced by ATP-dependent proteases such as the Clp system, which participates in protein quality control and degradation of damaged or misfolded proteins.

    “In cyanobacteria, proteostasis is strongly influenced by ATP-dependent proteases such as the Clp system, which participates in protein quality control and degradation of damaged or misfolded proteins [107].”

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Authors
Bouchnak, I., & van Wijk, K. J.
Affiliations
Cornell University (US)
Venue
Journal of Biological Chemistry
Publisher
Elsevier BV
Published
2021-01
Volume
296
Pages
100338
ISSN
0021-9258 (ISSN-L)
OpenAlex
W3121270487
Cited by
77
References
137
Citations by year
2026: 15 · 2025: 18 · 2024: 15 · 2023: 10 · 2022: 16 · 2021: 3
FWCI
3.45
Type
journal article
Language
en
Update notices
erratum (2022-03-01)
Open access
Locations
  • Journal of Biological Chemistry (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
Funders
National Science Foundation
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Heat shock proteins research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Photosynthetic Processes and Mechanisms
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Ubiquitin and proteasome pathways
Keywords
Clp protease, AAA+ ATPase, cyanobacteria, plastids, apicoplast, Plasmodium falciparum, protein unfolding, proteostasis, CLP, degron, plastid biogenesis, protein degradation, Synechocystis, Chlamydomonas, Arabidopsis
MeSH terms
Proteostasis, Cyanobacteria, Plasmodium falciparum, Substrate Specificity, Signal Transduction, Plastids, Proteomics, Endopeptidase Clp, Apicoplasts

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