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Biology subjects

D'Orazio, F. M.

Publications and source records attributed to D'Orazio, F. M..

2 recordsLinked to original sources

imAgeScore, a Cell Painting-Based Predictor of Cellular Age for High-throughput Drug Screening Applications

Quantifying cellular age in vitro in a scalable and biologically meaningful manner is essential for the discovery of pharmacological interventions that modulate aging. We developed imAgeScore, a machine-learning model trained on high-content Cell Painting features to predict the phenotypic age of primary human dermal fibroblasts. imAgeScore correlates with chronological and DNA methylation-based age estimates and captures coordinated morphological changes across nuclear and cytoplasmic compartments. The model detected age acceleration during serial propagation and age reduction following partial reprogramming. Pharmacological interventions targeting distinct aging hallmarks induced predictable shifts in predicted age and enabled classification of damaging versus rejuvenating cellular states. Application of imAgeScore in an automated high-throughput screening pipeline identified candidate age-modulating compounds, revealed inter-individual variability in response magnitude, and detected additive rejuvenation effects in selected combinatorial treatments. Functional validation in a scratch wound assay confirmed enhanced cellular repair by leading candidates, supporting the biological relevance of morphology-derived age reduction. Together, these results demonstrate that image-based morphological profiling provides a scalable platform for quantifying cellular aging and screening for candidate rejuvenation interventions.

cell biology↗

Germ plasm localisation dynamics mark distinct phases of transcriptional and post-transcriptional regulation control in primordial germ cells

In many animal models, primordial germ cell (PGC) development depends on maternally-deposited germ plasm to avoid somatic cell fate. Here, we show that PGCs respond to regulatory information from the germ plasm in two distinct phases and mechanisms in zebrafish. We show that PGCs commence zygotic genome activation together with the rest of the embryo with no demonstrable differences in transcriptional and chromatin accessibility levels. Thus, cytoplasmic germ plasm determinants only affect post-transcriptional stabilisation of RNAs to diverge transcriptome from somatic cells, which, unexpectedly, also activate germ cell-specific genes. Perinuclear relocalisation of germ plasm is coupled to dramatic divergence in chromatin opening and transcriptome from somatic cells characterised by PGC-specific chromatin topology. Furthermore, we reveal Tdrd7, regulator of germ plasm localisation, as crucial determinant of germ fate acquisition.

developmental biology↗