Bacteriophage genome-wide transposon mutagenesis.

July 23, 2026| Source: Cell

Bacteriophage genomes are densely packed with coding sequences and frequently encode genes of unknown function. Unbiased phage functional genomics approaches are therefore needed, particularly for large lytic phages. Here, we harness the mariner transposase to develop phage transposon mutagenesis and sequencing (phage TnSeq), which enables pooled sequencing to identify both fitness-conferring and dispensable genes. Using the Pseudomonas aeruginosa-infecting nucleus-forming jumbo phage ΦKZ (280,334 bp; 371 predicted genes), we show that ∼110 genes are fitness-conferring via phage TnSeq, identifying many known and previously unknown essential genes. Moreover, this phage harbors ∼261 non-essential genes, including some capsid and tail proteins, many of which are important for fitness across different clinical isolates or conditions. Phage TnSeq was also extended to a base-modified phage. Together, phage TnSeq is a scalable technology that can identify essential phage genes, generate knockouts in all non-essential genes, and sensitively assign the quantitative fitness contributions of every gene in parallel.

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An innervated and vascularized HNSCC-on-a-chip model built on defined and tunable engineered extracellular matrices.

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Health & MedicineNovember 3, 2026

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Health & MedicineNovember 3, 2026

DCAF6 reprograms TGF-β responses through TRIM33 destruction.

TGF-β signaling plays a pivotal role in regulating numerous cellular processes, primarily through the Smad-dependent pathway. Disruptions of the pathway are associated with developmental disorders and life-threatening diseases, such as cancer. It has been reported that TRIM33 inactivates Smad4 signaling and also drives its own signaling responses. However, the mechanism controlling TRIM33 activity has remained unclear. In this study, we identify DCAF6 as a previously unrecognized ubiquitin

Health & MedicineOctober 29, 2026

Stimulated protein degradation to promote mitochondrial function and neuronal survival.

Targeted protein degradation is a promising modality to treat cancer or inflammation, but whether it can provide a similar benefit for disorders caused by pervasive protein dysregulation is unclear. We describe stimulated protein degradation (SPD) as a strategy that leverages agonists of stress-responsive E3 ubiquitin ligases to simultaneously eliminate multiple pathogenic factors. Specifically, we show that activators of the reductive stress response E3 CUL2 FEM1B boost degradation of multiple