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Bright, N.

Publications and source records attributed to Bright, N..

2 recordsLinked to original sources

Shape2Fate: a morphology-aware deep learning framework for tracking endocytic and exocytic carriers at nanoscale.

Plasma membrane homeostasis requires balanced exocytosis and endocytosis, yet their coordination at the single-event level in non-neuronal cells is unresolved. We present Shape2Fate, a morphology-aware deep-learning pipeline that detects, tracks, and classifies individual exocytic and endocytic carriers in live-cell total internal reflection fluorescence structured illumination microscopy (TIRF-SIM) movies at [~]100 nm resolution. Trained on synthetic data and exploiting carrier shape evolution rather than fluorescence intensity, Shape2Fate achieves expert-level tracking and outcome classification across diverse cell types, imaging conditions, and microscope platforms. Applying Shape2Fate to constitutive secretion and insulin-stimulated GLUT4 exocytosis in adipocytes, we uncover two opposing exo-endocytic coupling architectures: exocytic fusion locally nucleates de novo clathrin-coated pits, whereas GLUT4 vesicles target pre-existing pits for rapid cargo capture. These findings establish that the spatial rules governing exo-endocytic coordination are not universal but are pathway-specific. Shape2Fate is openly available, enabling direct event-level mechanistic dissection of exo-endocytic coordination across pathways in living cells.

cell biology↗

Metagenomic Nanopore sequencing of influenza virus direct from clinical respiratory samples

Influenza is a major global public health threat as a result of its highly pathogenic variants, large zoonotic reservoir, and pandemic potential. Metagenomic viral sequencing offers the potential of a diagnostic test for influenza which also provides insights on transmission, evolution and drug resistance, and simultaneously detects other viruses. We therefore set out to apply Oxford Nanopore Technology to metagenomic sequencing of respiratory samples. We generated influenza reads down to a limit of detection of 102-103 genome copies/ml in pooled samples, observing a strong relationship between the viral titre and the proportion of influenza reads (p = 4.7x10-5). Applying our methods to clinical throat swabs, we generated influenza reads for 27/27 samples with high-to-mid viral titres (Cycle threshold (Ct) values <30) and 6/13 samples with low viral titres (Ct values 30-40). No false positive reads were generated from 10 influenza-negative samples. Thus Nanopore sequencing operated with 83% sensitivity (95% CI 67-93%) and 100% specificity (95% CI 69-100%) compared to the current diagnostic standard. Coverage of full length virus was dependent on sample composition, being negatively influenced by increased host and bacterial reads. However, at high influenza titres, we were able to reconstruct >99% complete sequence for all eight gene segments. We also detected Human Coronavirus and generated a near complete Human Metapneumovirus genome from clinical samples. While further optimisation is required to improve sensitivity, this approach shows promise for the Nanopore platform to be used in the diagnosis and genetic analysis of influenza and other respiratory viruses.

microbiology↗