Ubiquitylated proteins articles from across Nature Portfolio

p97/VCP, a nexus of the ubiquitin system, recognizes and unfolds ubiquitylated substrates via multiple cofactors. Here, the authors identify VCF1, a nuclear cofactor promoting p97 recruitment to, and proteasomal degradation of, ubiquitylated targets.

Studies using genetic screening, biophysical characterization and structural reconstitution elucidate the mechanism of action and enable rational design of a new class of functional compounds that glue target proteins to E3 ligases via intramolecularly bridging two domains to enhance intrinsic protein–protein interactions and promote target ubiquitination and degradation.

Here, the authors describe BioE3, a biotin-based method to discriminate direct substrates of ubiquitin E3 ligases of interest from mere interactors using proximity proteomics. BioE3 responds to chemical treatments, and works with RING- and HECT-type E3s, as well as ubiquitin-likes (e.g., SUMO).

The poly(ADP-ribosyl)transferases, tankyrase 1 and 2, are regulated by RNF146-mediated K48-linked polyubiquitylation and degradation. Here the authors show that this is opposed by K11-linked diubiquitylation by RING-UIM E3 ligases RNF114 and 166 and further impacted by several PAR-binding E3 ligases.

Overexpression of human antigen R (HuR) correlates with high grade tumours and poor patient prognosis. Here, the authors engineer a TRIM21 biological PROTAC to demonstrate the benefit of a targeted protein degradation approach to deplete HuR, resulting in tumour growth inhibition in pre-clinical cancer models by altering the HuR-regulated proteome.

FG-nucleoporins of the nuclear pore complexes form a permeability barrier between the nucleus and the cytosol. FG-nucleoporins contain disordered regions and are prone to aggregation. Two studies identify the chaperone DNAJB6 as a key factor that prevents aggregation of FG-nucleoporins and assists in the biogenesis of nuclear pore complexes.