Protein quality control and regulated proteolysis in the genome‐reduced organism Mycoplasma pneumoniae
Year: 2020
Type: article
Abstract: Protein degradation is a crucial cellular process in all-living systems. Here, using Mycoplasma pneumoniae as a model organism, we defined the minimal protein degradation machinery required to maintain proteome homeostasis. Then, we conditionally depleted the two essential ATP-dependent proteases. Whereas depletion of Lon results in increased protein aggregation and decreased heat tolerance, FtsH depletion induces cell membrane damage, suggesting a role in quality control of membrane proteins. An integrative comparative study combining shotgun proteomics and RNA-seq revealed 62 and 34 candidate substrates, respectively. Cellular localization of substrates and epistasis studies supports separate functions for Lon and FtsH. Protein half-life measurements also suggest a role for Lon-modulated protein decay. Lon plays a key role in protein quality control, degrading misfolded proteins and those not assembled into functional complexes. We propose that regulating complex assembly and degradation of isolated proteins is a mechanism that coordinates important cellular processes like cell division. Finally, by considering the entire set of proteases and chaperones, we provide a fully integrated view of how a minimal cell regulates protein folding and degradation.
Source: Molecular Systems Biology
Language: English
Topic: Heat shock proteins research
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $4,600
Funders: Centres de Recerca de Catalunya, European Commission, Generalitat de Catalunya, Institució Catalana de Recerca i Estudis Avançats, Ministerio de Ciencia e Innovación, Horizon 2020 Framework Programme, Instituto de Salud Carlos III, European Regional Development Fund, H2020 European Research Council
OpenAlex ID: W3112326989