Protein quality control

  • Article
    | Open Access

    Misfolded proteins are ubquitinated and subsequently condensed by cargo receptors for selective autophagy. Here, the authors use in vitro reconstitution to elegantly dissect how the receptors p62/SQSTM1, NBR1 and TAX1BP1 contribute to p62-ubiquitin condensate formation and degradation by autophagy.

    • Eleonora Turco
    • , Adriana Savova
    •  & Sascha Martens
  • Article
    | Open Access

    Existing methods for inflicting cellular heat shock are limited by the time delay in achieving the desired temperature and the spatial precision that can be achieved. Here the authors report a method to induce focused thermal protein damage using plasmonic silver nanoparticles.

    • Martin Mistrik
    • , Zdenek Skrott
    •  & Jiri Bartek
  • Article
    | Open Access

    ClpXP is the main ATP-dependent proteolytic complex in bacteria, is essential for maintaining cellular protein homeostasis and is also critical for bacterial pathogenesis. Here, the authors establish a functional link between ClpXP and trigger actor, a chaperone involved in the early stages of protein folding.

    • Kamran Rizzolo
    • , Angela Yeou Hsiung Yu
    •  & Walid A. Houry
  • Article
    | Open Access

    Unlike canonical macroautophagy, alternative autophagy does not require the factors Atg5 and Atg7. Here, the authors show that Wipi3 is essential for alternative autophagy, but not for canonical autophagy, and that Wipi3 functions to maintain neuronal cells via mechanisms different from those of canonical autophagy.

    • Hirofumi Yamaguchi
    • , Shinya Honda
    •  & Shigeomi Shimizu
  • Article
    | Open Access

    Maintenance and quality control of the mitochondrial respiratory chain complexes responsible for bulk energy production are unclear. Here, the authors show that the mitochondrial protease ClpXP is required for the rapid turnover of the core N-module of respiratory complex I, which happens independently of other modules in the complex.

    • Karolina Szczepanowska
    • , Katharina Senft
    •  & Aleksandra Trifunovic
  • Article
    | Open Access

    Genes encoding protein complex subunits are often dispersed in the genome of eukaryotes, raising the question how these protein complexes assemble. Here, the authors provide evidence that mammalian nuclear transcription complexes are formed co-translationally to ensure specific and functional interactions.

    • Ivanka Kamenova
    • , Pooja Mukherjee
    •  & László Tora
  • Article
    | Open Access

    Ischemic reperfusion or nutrient deprivation that produces reactive oxygen species can lead to a loss of muscle contractile function. Here the authors show that glutathionylation of the lysine methyltransferase SMYD2 contributes to degradation or disassembly of sarcomeres.

    • Dhanushka N. P. Munkanatta Godage
    • , Garrett C. VanHecke
    •  & Young-Hoon Ahn
  • Article
    | Open Access

    The ribosome-associated quality control complex (RQC) functions to disassemble stalled ribosomes. Here the authors find that the tRNA hydrolase Vms1 is involved in the release of nascent peptide from stalled ribosomes.

    • Olga Zurita Rendón
    • , Eric K. Fredrickson
    •  & Jared Rutter
  • Article
    | Open Access

    The U-box ubiquitin ligase UFD-2 is one of the most abundant components of the ubiquitin proteasome system in muscle cells. Here the authors perform in vitro and in vivo experiments and show that UFD-2 has E3 ligase activity and that it ubiquitinates unfolded myosin using the C. elegans myosin chaperone UNC-45 as an adaptor protein.

    • Doris Hellerschmied
    • , Max Roessler
    •  & Tim Clausen
  • Article
    | Open Access

    MepS is a peptidoglycan (PG) cross-link specific hydrolase needed for cell wall expansion and its cellular levels must be tightly regulated. Here the authors present the structure of the MepS degrading protease Prc bound to its adaptor NlpI and propose a model how the NlpI-Prc complex mediates MepS degradation.

    • Ming-Yuan Su
    • , Nilanjan Som
    •  & Chung-I Chang
  • Article
    | Open Access

    Several protein quality control mechanisms are in place to trigger the rapid degradation of aberrant polypeptides and mRNAs. Here the authors describe a mechanism of ribosome-mediated quality control that involves the ubiquitination of ribosomal proteins by the E3 ubiquitin ligase Hel2/RQT1.

    • Yoshitaka Matsuo
    • , Ken Ikeuchi
    •  & Toshifumi Inada