Biology subjects

Bonadonna, M.

Publications and source records attributed to Bonadonna, M..

6 recordsLinked to original sources

bioRxiv2026

A mobile optical coherence microscope for studying aquatic organisms in- and outside the laboratory

High-resolution, three-dimensional imaging of live organisms has largely depended on laboratory-bound microscopes, limiting quantitative analysis of morphology and dynamics to species that survive transport and thrive under lab-controlled conditions. Here we present a mobile optical coherence microscopy (OCM) platform that overcomes this constraint, delivering [~]2.5 {micro}m axial resolution, label-free, volumetric imaging of live aquatic organisms in both laboratory and remote field environments. We demonstrate the platform across a broad range of aquatic organisms from the lab and field, spanning multiple phyla - including cnidarians, poriferans, annelids, arthropods and echinoderms - resolving internal anatomy, tissue boundaries and organismal morphology at micrometer scale without fixation, fluorescent labeling, or specialized sample preparation. High-speed acquisition, with up to 250 kHz A-line rate and 7.7 Hz volume rate, further enabled morphodynamic imaging of live biological processes, including cellular aggregate motility, embryonic cell division, and organ-level peristaltic dynamics in intact, living animals. To demonstrate field deployability, the platform was operated during the EMBL TREC pan-European expedition, enabling on-site, label-free imaging of marine organisms and plankton immediately upon collection. By decoupling high-resolution volumetric imaging from fixed laboratory settings, mobile OCM opens a path toward field-ready quantitative morphological and dynamic phenotyping of aquatic life.

bioengineering↗

bioRxiv2026

Multi-modal single-cell profiling reveals transcriptional states and commitment dynamics during sexual reproduction in the diatom Pseudo-nitzschia multistriata

Diatoms, single-celled photosynthetic eukaryotes, traditionally considered primarily influenced by resource availability, are now recognized to exhibit complex developmental processes reminiscent of those in multicellular organisms. Sexual reproduction is an obligate choice in many species, albeit with variable frequency and efficiency. In order to explore decision making mechanisms and cellular heterogeneity inherent to this specific phase of the diatom life cycle, we applied a multi-modal strategy to follow sexual reproduction events in the model diatom Pseudo-nitzschia multistriata: i) we employed image-enabled cell sorting to link sexual stages morphology with gene expression ii) we developed a single-nucleus RNA sequencing assay, and iii) conducted proteomic profiling. Combining phenotypes with single-cell profiling allowed us to identify sexual state-specific transcription programs and different states within morphologically identical parental cells, revealing a widespread commitment of the majority of the population to sexual reproduction. This implies that the bottleneck to successful sexual reproduction in this species can be placed downstream of the signalling phase between mating cells, with additional, yet unidentified, factors influencing mating success at sea.

microbiology↗

bioRxiv2026

An Advanced Mobile Laboratory to enable field-based microbial ecology and cell biology across scales

Microbial biodiversity is central to ecosystem function, yet mechanistic insights into the cell biology of environmental organisms remain limited. The underlying challenges are twofold: most microbes remain uncultivable, and a persistent gap exists between field sampling and laboratory analyses. Here, we introduce the Advanced Mobile Laboratory (AML), a field-deployable platform that integrates confocal microscopy, image-enabled cell sorting, and cryo-preparation for expansion and electron microscopy. This setup enables immediate, standardized processing and analysis of environmental communities directly at the sampling site. We demonstrate its capability using marine eukaryotic plankton, showing how the AML enables multiscale investigations, from live imaging of natural communities to enabling ultrastructural and single-cell omics analyses, while minimizing sample degradation and enabling on-site experimentation. By bringing high-end sample preparation and analytical capacity into the field, the AML enables studying life in its natural context to mechanistically understand lifes diversity in the environment.

cell biology↗

bioRxiv2022

IRON REGULATORY PROTEIN (IRP)-MEDIATED IRON HOMEOSTASIS IS CRITICAL FOR NEUTROPHIL DEVELOPMENT AND DIFFERENTIATION IN THE BONE MARROW

Iron is mostly devoted to the hemoglobinization of erythrocytes for oxygen transport. Yet, emerging evidence points to a broader role for the metal in hematopoiesis, including the formation of the immune system. Iron availability in mammalian cells is controlled by iron-regulatory proteins (IRP)-1 and -2. We report that global disruption of both IRP1 and IRP2 in adult mice impairs neutrophil development and differentiation in the bone marrow, yielding immature neutrophils with abnormally high glycolytic and autophagic activity, resulting in neutropenia. IRPs promote neutrophil differentiation in a cell intrinsic manner by securing cellular iron supply together with transcriptional control of neutropoiesis to facilitate differentiation to fully mature neutrophils. Unlike neutrophils, monocyte count was not affected by IRP and iron deficiency, suggesting a lineage-specific effect of iron on myeloid output. This study unveils the previously unrecognized importance of IRPs and iron metabolism in the formation of a major branch of the innate immune system.

immunology↗

bioRxiv2022

Plasma iron controls neutrophil production and function

Low plasma iron (hypoferremia) induced by hepcidin is a conserved inflammatory response that protects against infections but inhibits erythropoiesis. How hypoferremia influences leukocytogenesis is unclear. Using proteomic data, we predicted that neutrophil production would be profoundly more iron-demanding than generation of other white blood cell types. Accordingly in mice, hepcidin-mediated hypoferremia substantially reduced numbers of granulocytes but not monocytes, lymphocytes or dendritic cells. Neutrophil rebound after anti-GR1-induced neutropenia was blunted during hypoferremia, but was rescued by supplemental iron. Similarly, hypoferremia markedly inhibited pharmacologically-stimulated granulopoiesis mediated by GCSF and inflammation-induced accumulation of neutrophils in the spleen and peritoneal cavity. Furthermore, hypoferremia specifically altered neutrophil effector functions, suppressing antibacterial mechanisms but enhancing mitochondrial ROS-dependent NETosis associated with chronic inflammation. Notably, antagonising endogenous hepcidin during acute inflammation enhanced production of neutrophils. We propose plasma iron modulates the profile of innate immunity by controlling monocyte-to-neutrophil ratio and neutrophil activity in a therapeutically targetable system.

immunology↗

bioRxiv2020

Control of Systemic Iron Homeostasis by the 3' Iron-Responsive Element of Divalent Metal Transporter 1 in Mice.

Divalent metal transporter 1 (DMT1) is essential for dietary iron assimilation and erythroid iron acquisition. The 3 untranslated region of the murine DMT1 mRNA contains an iron responsive element (IRE) that is conserved in humans but whose functional role remains unclear. We generated and analyzed mice with targeted disruption of the DMT1 3IRE. These animals display hypoferremia during the suckling period, associated with a reduction of DMT1 mRNA and protein in the intestine. In contrast, adult mice exhibit hyperferremia, accompanied by enlargement of hepatic and splenic iron stores. Intriguingly, disruption of the DMT1 3IRE in adult animals augments intestinal DMT1 expression, in part due to increased mRNA translation. Hence, during postnatal growth, the DMT1 3IRE promotes intestinal DMT1 expression and secures iron sufficiency; in adulthood, it suppresses DMT1 and prevents systemic iron loading. This work demonstrates that the 3IRE of DMT1 plays a role in the control of DMT1 expression and systemic iron homeostasis, and reveals an age-dependent switch in its activity. Key pointsO_LITargeted mutagenesis of the 3IRE of DMT1 in mice reveals its importance for maintenance of systemic iron homeostasis. C_LIO_LIThe 3IRE stimulates intestinal DMT1 expression and prevents hypoferremia during early life, but exerts opposite effects in adulthood C_LI

molecular biology↗