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The study identifies a cellular defense pathway, named LORD (Lipid Oxygen Radical Defense), that protects cells from lipid oxidation and ferroptosis through an epigenetically regulated program linking oxidative stress sensing to redox homeostasis and cell survival.

Pore-forming toxins (PFTs) are produced as virulence factors by many pathogenic bacteria. In this Review, Dal Peraro and van der Goot describe new mechanistic insights into the assembly of these toxins and their target specificity, and discuss recent therapeutic developments.

The fusogenic activity of SARS-CoV-2 Spike depends on its post-translational lipid modification by host S-acyltransferases, predominantly ZDHHC20. Here, Mesquita and Abrami et al. show that SARS-CoV-2 infection and colitis in mice induce a damage response resulting in an altered version of the ZDHHC20 enzyme that is more abundant and significantly more efficient at attaching fatty acids to viral Spike.

Recent advances have shed light on the interactions that occur between pathogens and endocytic pathway components. With the aim of generating suitable replication niches, microorganisms use existing cellular pathways and have developed selective and manipulative behaviour to avoid lysosome-mediated killing.

Acyl protein thioesterase APT2 interacts with membranes via its charged β-tongue, becomes palmitoylated by ZDHHC3/7 and deforms the bilayer to extract substrate acyl chains. APT2 deacylation leads to its membrane release and degradation.

A key player in the formation of endoplasmic reticulum sheets is CLIMP-63, but mechanistic details remained elusive. Here authors combined cellular experiments and mathematical modelling to show that S-acylation of CLIMP-63 regulates its function by mediating its oligomerisation, turnover, and localisation.

Certain pathogens and bacterial toxins exhibit exquisite host specificity, the determinants of which often remain mysterious. A recent report shows that the human specificity of the pore-forming toxin intermedilysin (ILY), a member of the cholesterol-dependent cytolysins (CDCs), is due to its specific interaction with the human cluster of differentiation protein CD59.

How palmitoylated proteins specifically localize is not fully understood. Here, authors created the SwissKASH assay to visualize S-palmitoylation in cells and uncovered a striking substrate selectivity of acyltransferases at the core of this process.

Aerolysin is a secreted bacterial pore forming toxin that inserts into the host plasma membrane, potentially leading to cell death. Here the authors present Cryo-EM structures of aerolysin arrested at different stages of the pore formation process that provide insight into the conformational changes that allow pore formation.

Hyaline fibromatosis syndrome (HFS) is a hereditary disease characterized by nodular cutaneous lesions and joint pain. Here Bürgiet al. show that CMG2/ANTXR2 regulates collagen VI abundance, with loss-of-function mutations promoting collagen VI accumulation in HFS nodules and myometrial collagen deposition and sterility in mice, which can be rescued by depleting collagen VI.

S-palmitoylation regulation has been studied mostly in the cytosol and its role in mitochondria is unclear. Here the authors develop fluorescent mitochondria-targeted probes and find that depalmitoylation occurs in mitochondria and it’s influenced by alterations in mitochondrial lipid homeostasis.

Near-atomistic models of the prepore and membrane-inserted pore conformations derived from a combination of crystallography, cryo-EM, single-particle analysis, molecular simulation and modeling reveal a swirling mechanism of membrane insertion and pore formation by aerolysin.

Super-resolution optical fluctuation imaging provides 3D images of biological specimens via blinking fluorophores. Geissbuehler et al. present a multiplexed version of this method that captures images at multiple focal planes simultaneously, reducing the acquisition time compared with standard approaches.

Protein S-acylation is involved in many pathophysiological processes. Here, Mesquita et al. discuss the structure, function and regulation of S-acylation and deacylation enzymes and describe how this post-transcriptional modification precisely controls protein–cell membrane interactions. Potential therapeutic applications of S-acylation are also highlighted.

The discovery and characterization of small-molecule antagonists that inhibit the stimulator of interferon genes (STING) protein may help to develop therapies for the treatment of autoinflammatory disease.

The Wnt/planar cell polarity (Wnt/PCP) pathway orients cell division in various developmental contexts including zebrafish gastrulation. Gonzalez-Gaitan and colleagues reveal that, downstream of Wnt/PCP, the anthrax toxin receptor 2a interacts with actin to form a cortical actin cap in dorsal epiblast cells, and acts through RhoA and the formin zDia2 to orient the mitotic spindle.

Existing methods used for peptide analysis suffer from low sensitivity and specificity. Here the authors demonstrate the nanopore-based size-discrimination and purity analysis of short homopolymeric peptides with a single amino acid resolution.