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Biology subjects

Donato, C.

Publications and source records attributed to Donato, C..

4 recordsLinked to original sources

Releasing RNA from formalin: novel 20th century rotavirus alphagastroenteritidis strains identified in Australian microbat voucher specimens

Archival specimens held in biorepositories (e.g. natural history collections) offer rare temporal snapshots of global biodiversity. These collections not only preserve species morphology and aspects of ecology, but increasingly provide access to historical molecular data, including insights into wildlife disease. As several pandemics have originated from animal viruses spilling over into the human population (i.e., SARS-CoV-2/COVID-19, 2009 H1N1 influenza, and HIV/AIDS), characterising the diversity of viruses circulating in wildlife populations is essential for proactive pandemic preparedness. Yet, current surveillance remains biased toward contemporary viruses of economic importance. One solution to bridging spatiotemporal gaps in wildlife virus knowledge is retrospective screening of vouchered wildlife specimens. However, such efforts have been hindered by formalin fixation of specimens, which degrades and cross-links nucleic acids. Here we demonstrate that formalin-fixed vouchered wildlife specimens retain both host and viral RNA fragments after being stored for up to sixty years. We recovered fragments of divergent strains of Rotavirus alphagastroenteritidis from two Australian microbat species; Nyctophilus geoffroyi (lesser long-eared bat) and Rhinolophus megaphyllus (smaller horseshoe bat), representing the first characterisation of Rotavirus alphagastroenteritidis in Australian bats, and the oldest identification of the virus to date. Concurrently, we sequenced endogenous host RNA, providing a proof-of- concept for dual host-virus transcript recovery from vouchered specimens. This study highlights the role biorepositories can play in reconstructing historical viral landscapes and enabling spatiotemporal host-virus insight to advance both biodiversity science and global pandemic preparedness.

genomics↗

Tracing Endometriosis: Coupling deeply phenotyped, single-cell based Endometrial Differences and AI for disease pathology and prediction

Endometriosis, affecting 1 in 9 women, presents treatment and diagnostic challenges. To address these issues, we generated the biggest single-cell atlas of endometrial tissue to date, comprising 466,371 cells from 35 endometriosis and 25 non-endometriosis patients without exogenous hormonal treatment. Detailed analysis reveals significant gene expression changes and altered receptor-ligand interactions present in the endometrium of endometriosis patients, including increased inflammation, adhesion, proliferation, cell survival, and angiogenesis in various cell types. These alterations may enhance endometriosis lesion formation and offer novel therapeutic targets. Using ScaiVision, we developed neural network models predicting endometriosis of varying disease severity (median AUC = 0.83), including an 11-gene signature-based model (median AUC = 0.83) for hypothesis-generation without external validation. In conclusion, our findings illuminate numerous pathway and ligand-receptor changes in the endometrium of endometriosis patients, offering insights into pathophysiology, targets for novel treatments, and diagnostic models for enhanced outcomes in endometriosis management.

molecular biology↗

Molecular signature and target-specificity of inhibitory circuits formed by Martinotti cells in the mouse barrel cortex

In the neocortex, fast synaptic inhibition orchestrates both spontaneous and sensory-evoked activity. GABAergic interneurons (INs) inhibit pyramidal neurons (PNs) directly, modulating their output activity and thus contributing to balance cortical networks. Moreover, several IN subtypes also inhibit other INs, forming specific disinhibitory circuits, which play crucial roles in several cognitive functions. Here, we studied a homogeneous subpopulation of somatostatin (SST)-positive INs, the Martinotti cells (MCs) in layer 2/3 of the mouse barrel cortex (both sexes). MCs are a prominent IN subclass inhibiting the distal portion of PN apical dendrites, thus controlling dendrite electrogenesis and synaptic integration. Yet, it is poorly understood whether MCs inhibit other elements of the cortical circuits, and the connectivity properties with non-PN targets are unknown. We found that MCs have a strong preference for PN dendrites, but they also considerably connect with parvalbumin (PV)-positive, vasoactive intestinal peptide (VIP)-expressing and layer 1 (L1) INs. Remarkably, GABAergic synapses from MCs exhibited clear cell-type-specific short-term plasticity. Moreover, whereas the biophysical properties of MC-PN synapses were consistent with distal dendritic inhibition, MC-IN synapses exhibited characteristics of fast perisomatic inhibition. Finally, MC-PN connections used 5-containing GABAARs, but this subunit was not expressed by the other INs targeted by MCs. We reveal a specialized connectivity blueprint of MCs within different elements of superficial cortical layers. In addition, our results identify 5-GABAARs as the molecular fingerprint of MC-PN dendritic inhibition. This is of critical importance, given the role of 5-GABAARs in cognitive performance and their involvement in several brain diseases. Significance statementMartinotti cells (MCs) are a prominent subclass of SST-expressing GABAergic INs, specialized in controlling distal dendrites of PNs and taking part in several cognitive functions. Here we characterize the connectivity pattern of MCs with other INs in the superficial layers (L1 and L2/3) of the mouse barrel cortex. We found that the connectivity pattern of MCs with PNs as well as PV, VIP and L1 INs exhibit target-specific plasticity and biophysical properties. The stark specificity of 5-GABAARs at MC-PN synapses, and the lack or functional expression of this subunit by other cell types, define the molecular identity of MC-PN connections and the exclusive involvement of this outstanding inhibitory circuits in 5-dependent cognitive tasks.

neuroscience↗

Alterations of specific inhibitory circuits of the prefrontal cortex underlie abnormal network activity in a mouse model of Down syndrome

Down syndrome (DS) results in various degrees of cognitive deficits. In DS mouse models, recovery of behavioral and neurophysiological deficits using GABAAR antagonists led to hypothesize an excessive activity of inhibitory circuits in this condition. Nonetheless, whether over-inhibition is present in DS and whether this is due to specific alterations of distinct GABAergic circuits is unknown. In the prefrontal cortex of Ts65Dn mice (a well-established DS model), we found that the dendritic synaptic inhibitory loop formed by somatostatin-positive Martinotti cells (MCs) and pyramidal neurons (PNs) was strongly enhanced, with no alteration of their excitability. Conversely, perisomatic inhibition from parvalbumin-positive (PV) interneurons was unaltered, but PV cells of DS mice lost their classical fast-spiking phenotype and exhibited increased excitability. These microcircuit alterations resulted in reduced pyramidal-neuron firing and increased phase locking to cognitive-relevant network oscillations in vivo. These results define important synaptic and circuit mechanisms underlying of cognitive dysfunctions in DS.

neuroscience↗