Volume 14 Issue 5, May 2018

Proteins brought to an E3 ubiquitin ligase are polyubiquitylated for rapid degradation via the proteasome. A new study developed a tag-based degradation system using heterobifunctional degradation inducers called dTAGs, which rapidly depleted FKBP12^F36V-fused proteins in cultured cells and in mice.

Regulated destruction of proteins underlies just about everything a cell does. A structural study of human Gid4, the N-recognin of the Pro/N-end rule pathway that targets proteins through their N-terminal proline, illuminates the recognition of substrates by this proteolytic system.

Through molecular grafting, cyclic disulfide-rich peptides can be used as scaffolds to improve the stability, rigidity, and cellular uptake of bioactive peptides, although a number of factors should be considered when designing such grafted peptides.

The crystal structure of a methyltransferase domain embedded within an interrupted adenylation domain provides insight into how a nonribosomal peptide synthetase N-methylates amino acid precursors for their incorporation into the peptide product.

The dTAG system pairs potent heterobifunctional degraders and extensible tagging strategies to achieve immediate and reversible degradation of divergent proteins, facilitating biological investigation and drug target validation in cells and in mice.

The biosynthesis and secretion of redox-active coumarins sideretin and fraxetin in Arabidopsis thaliana enables the plant to acquire iron under nutrient-limited conditions and provides a blueprint for the use of related compounds in other eudicots.

The source of biological toluene production in diverse anoxic microbial communities is a glycyl radical enzyme that catalyzes phenylacetate decarboxylation (PhdB), and its cognate activating radical S-adenosylmethionine enzyme (PhdA).

Post-translational modification of residues in an intrinsically disordered region of Bcl-XL promotes interactions with its folded core and allosterically reduces affinity for proapoptotic BH3-domain-containing proteins, resulting in apoptosis.

Crystal structures of a subunit of the ubiquitin ligase complex serving the N-end rule pathway of degrons marked by proline define a degron recognition mechanism and selection criteria for substrates.

The crystal structure and cryo-electron microscopy of the loading/condensing region of a nonreducing polyketide synthase reveals the insertion of a starter-unit acyltransferase into the condensing region and an asymmetrical post-loading state.

The jasmonoyl-isoleucine (JA-Ile) receptor COI1 is functionally conserved between the bryophyte Marchantia polymopha and the eudicot Arabidopsis thaliana, with two isomers of the JA-Ile precursor dinor-OPDA acting as the ligand for Marchantia COI1.

A single-molecule forced unfolding of E. coli chloride transporter ClC-ec1 shows that the N- and C-terminal halves of the protein unfold independently, with exposed polar surfaces stabilized by membrane lipid head groups and water.

Dissolved oxygen and a reducing-plus-oxidizing system suppress photobleaching and photoblinking in single-molecule tracking experiments, allowing long recordings of CD47 and integrin that showed temporary immobilization within focal adhesions.

FINO₂ is a small molecule that requires the endoperoxide moiety and hydroxyl group to promote ferroptosis through indirect inhibition of GPX4 enzymatic function and direct oxidation of iron, resulting in increased lipid peroxidation.

Comprehensive glycome profiling of immunoglobulin G (IgG) in 95 strains of mice from the Collaborative Cross genetics resource reveals the extent and variability of IgG glycosylation in vivo.