Volume 20 Issue 5, May 2024

Genetically encoded tools to manipulate redox metabolism are in high demand for investigating the underlying mechanism of cofactor imbalances in mammalian systems. A new tool enables the induction and interrogation of NADH reductive stress.

A second-timescale optogenetic strategy DeKinomics was developed, enabling the study of downstream events of kinases in a gain-of-function manner. Using this technique, UBA1, an E1 enzyme that initiates the ubiquitination cascade, was found to be directly regulated by tyrosine phosphorylation.

Ribosomally synthesized and post-translationally modified peptide (RiPP) natural products typically rely on substrate recognition through remote protein–protein interaction sites. Now, an atypical dehydratase, whose activity is directed by neighboring azole modifications, has been shown to produce a highly modified peptide hybrid bearing dehydroamino acids, enabling the synthesis of members of the dehydrazole family of RiPPs.

Peptide vaccines use antigenic peptide fragments to induce an immune response but are problematic because of the short half-life of peptides. A study now reports thioamide substitution in the peptide backbone as a strategy to enhance resistance to proteolysis and promote binding to the MHC I complex for T cell activation.

Cyclic peptides can bind challenging disease targets, but their oral application is hindered by digestion and absorption issues. We developed a versatile method for the synthesis and functional screening of vast numbers of synthetic cyclic peptides and identified peptides with high inhibitory activity, stability and oral bioavailability in rats.

O-linked N-acetylglucosamine (O-GlcNAc) is an endogenous form of glycosylation that alters the structure of α-synuclein amyloid fibrils and attenuates their pathogenetic properties. The modified fibrils have a significantly reduced ability to seed the aggregation of endogenous α-synuclein in cultured neurons and in mice brains in vivo, which results in reduced pathology.

Hanswillemenke, Hofacker and colleagues developed a proximity labeling-based method to identify protein interactome of small molecules and RNA drugs within living cells, facilitating the design and development of RNA drugs with enhanced pharmacological properties.

A chemical screen identified a small molecule inhibitor of CHEK2 that boosts insulin secretion in human β cells, including those from both healthy and type 2 diabetic human islets, as well as in diabetic mouse models and cynomolgus macaques.

Chemical proteomics profiling of 1,183 kinase inhibitors from past drug discovery projects revealed a large number of reasonably selective compounds for several kinases such as SYK and CK2.

Development of chemically responsive bandpass filters mimics the signal-processing abilities of electronic circuits in mammalian cells by responding to chemical concentrations within a specific range and rejecting ones outside that range.

A soluble bacterial transhydrogenase from Escherichia coli (EcSTH) was validated as a genetically encoded tool to induce NADH reductive stress in mammalian cells revealing unique transcriptional and metabolic signatures.

The plant AUG-stop element in the 5′ UTR acts as a boron concentration sensor, regulating downstream ORF translation. Here, structural and biochemical analyses show that a high concentration of borate fixes eRF1 on 80S ribosomes, preventing sliding through downstream of AUG-stop elements.

Weng et al. developed a photocaged lysine-based gain-of-function strategy termed DeKinomics to systematically dissect kinase activity with high specificity and temporal resolution under living conditions.

Cyclic peptides show promise for modulating difficult disease targets; however, they often cannot be administered orally. The authors developed a method to synthesize and screen large libraries of small cyclic peptides while enabling the simultaneous interrogation of activity and permeability. This approach was applied to the disease target thrombin to discover peptides with high affinity, stability and oral bioavailability of up to 18% in rats.

Developing disease-modifying drugs for neurodegenerative diseases has been very challenging. Now a machine learning approach has been used to identify small molecule inhibitors of α-synuclein aggregation, a process implicated in Parkinson’s disease and other synucleinopathies. Compounds that bind to the catalytic sites on the surface of the aggregates were identified and then progressively optimized into secondary nucleation inhibitors.

α-Synuclein and tau can form multiple amyloid structures or strains that are associated with different neurodegenerative diseases, suggesting a strain–toxicity relationship. Now, it has been shown that O-GlcNAc modification of α-synuclein results in the formation of an amyloid strain that is largely nonpathogenic in vivo, supporting structure-dependent toxicity and another protective role for O-GlcNAc.