Research Briefing

A new engineering strategy for improving the biosynthesis of secondary metabolites in Streptomyces has been developed through the analysis of genes co-evolved with biosynthetic gene clusters. This strategy has been verified in 11 Streptomyces strains to enhance production of 16,385 metabolites, showing potential applications in drug discovery and industrial production.

A new sensor that detects optoacoustic signals generated by mid-infrared light enables measurement of glucose concentration from intracutaneous tissue rich in blood. This technology does not rely on glucose measurements in interstitial fluid or blood sampling and might yield the next generation of non-invasive glucose-sensing devices for improved diabetes management.

AMPK directly phosphorylates the mitochondrial protein SYNJ2BP to facilitate its interaction with the RNA-binding protein SYNJ2a, which transports Pink1 mRNA into neurites. AMPK inhibition downstream of insulin signalling untethers Pink1 mRNA from neuronal mitochondria and favours PINK1-dependent mitophagy in neurons. ApoE4-induced insulin receptor internalization reverses the process by stabilizing Pink1 mRNA binding to neuronal mitochondria.

Individuals with osteoporosis have increased risk of Alzheimer’s disease or cognitive impairment during ageing. We elucidated a partial explanation for bone dysmetabolism’s association with such cognitive decline, by demonstrating how elevated sclerostin secretion from osteocytes in bone impaired cognitive function in aged mice and in an Alzheimer’s disease mouse model.

Glycerol-3-Phosphate (G3P) and phosphoethanolamine (pEtN) biosynthetic pathways are modulated during senescence establishment to sustain lipid droplet accumulation and senescence-associated secretome. These findings reveal new targets for an immunomodulatory approach against senescent cells.

Here, we reveal functional heterogeneity among β cells and discover that readily releasable β cells (RRβs) are a subpopulation that disproportionally contributes to biphasic glucose-stimulated insulin secretion. We further show that the dysfunction of RRβs has a crucial role in the progression of diabetes.

Murine blastocysts and embryonic stem cells mimicking the pre-implantation epiblast import extracellular protein through macropinocytosis and engage a robust lysosomal digestive programme to meet their nutrient demands. We found that as development proceeds, post-implantation epiblast-like cells downregulate protein digestion, increase expression of amino acid transporters and become dependent on soluble amino acids.

Calcium sensing receptor (CaSR) and peptide transporter 1 (PepT1) have been implicated in protein sensing in the gut, although the mechanisms are poorly understood. We find that, in the small intestine, CasR and PepT1 are necessary for protein sensing to regulate gut peptide release, feeding and glucose tolerance in rats in vivo.

Macrophages that clear apoptotic cells (efferocytosis) proliferate to enhance tissue repair and resolution. Here, we find that a previously elucidated nucleotide ‘cargo’ proliferation pathway that increases Myc mRNA is complemented by efferocytosis-induced lactate, which stabilizes Myc protein through SIRT1-mediated Myc protein deacetylation.

We demonstrated increased phospholipid peroxidation due to the formation of monolysocardiolipin–cytochrome c complexes in tafazzin-deficient models of Barth syndrome. We found that a specific anti-peroxidase agent inhibited this complex and improved mitochondrial respiration. Thus, targeting the deleterious peroxidase activity offers a potential therapeutic approach to treat Barth syndrome.

Analysis of cells shed from the mouse gut, using bulk and single-cell transcriptomics, as well as single-molecule FISH and intravital imaging, revealed that shed cells are diverse, remain viable for a few hours and upregulate anti-microbial gene expression programs.

The molecular underpinnings of the extensive cellular, morphological and functional plasticity of skeletal muscle in exercise training are poorly understood. We have now begun to unravel the complex epigenetic, transcriptional and proteomic networks that determine the muscle response to exercise in a manner depending on the training state.

Glucagon-like peptide 1 (GLP-1) controls insulin secretion and body weight through activation of its receptor, GLP1R. Large-scale functional analysis of 60 GLP1R genetic variants revealed that loss-of-function (LoF) phenotypes, in particular of cell surface expression, are associated with impaired glucose control and increased adiposity.

A mouse pancreatic islet atlas comprising over 300,000 single-cell transcriptomes was integrated from nine biologically diverse datasets to unify existing knowledge in the islet biology community. This interactively accessible resource reveals new insights into the molecular identity and plasticity of islet and β-cells across sex, life span and diabetes progression.

Sensory association learning is impaired in people with insulin resistance but can be restored following a one-time intervention with liraglutide. These findings provide ample evidence for metabolic signals as modulators of adaptive behaviour and suggest a potential role for GLP-1 receptor agonists in obesity management.

By using a combination of transcriptomics, primary adipocyte culture and experimental medicine approaches, we identified the sodium-dependent serotonin transporter SERT as a novel regulator of human brown adipose tissue function.

This study shows that a 10% weight loss induced by calorie restriction and multimodal exercise training results in a much greater increase in whole-body insulin sensitivity than matched weight loss induced by calorie restriction alone. This result underscores the importance of adding regular exercise to a weight loss programme, as it improves metabolic health.

This study reveals that oxidative aneuploid cancer cells exhibit an upsurge of NADPH levels during mitosis, which neutralizes excessive reactive oxygen species and protects against chromosome mis-segregation.

Comparative metabolomic analyses of the guts of healthy colonized versus germ-free mice helped map microbial metabolites across the various intestinal niches. The microbial origin and biochemical processes underlying several metabolites could be inferred, even in areas difficult to access, such as the small intestine.

Obesity is caused by a mismatch between energy intake and expenditure. How much reduced expenditure (which is assumed to result from reduced activity) or elevated food intake contribute to obesity is debated. We show that total energy expenditure has been falling owing to a reduction in basal metabolic rate and not in activity expenditure.