Biology subjects

Capra, E.

Publications and source records attributed to Capra, E..

5 recordsLinked to original sources

bioRxiv2026

Human basal radial glia morphotypes are transcriptionally distinct and exhibit different cell fate determination

Basal radial glia (bRG) are key neural progenitors driving human neocortical expansion. They exhibit remarkable morphological heterogeneity, yet the stability and functional significance of their distinct morphotypes remains unclear. Using human cortical brain organoids combined with long-term live imaging and morphology-resolved spatial transcriptomics (CellShape-seq), we show that bRG morphotypes display distinct morphodynamic behaviors, proliferative capacities and transcriptional profiles. While bifurcated bRG remodel extensively during mitosis to produce morphologically diverse progeny, multipolar cells are most morphologically flexible during interphase. Multipolar bRG further show the greatest proliferative capacity and the transcriptional signature related to progenitor state. Bifurcated bRG are least proliferative and are enriched for the multifunctional gene expression regulator YBX1. Pharmacological inhibition of YBX1 depletes bifurcated bRG, reduces neurogenesis, and promotes glial commitment. Our findings link progenitor morphology, gene expression and fate, providing a framework for understanding the cellular logic of human cortical development.

neuroscience↗

bioRxiv2025

Human-specific morphoregulatory signatures in basal radial glia characterize neocortex evolution

As the seat of our cognition, the human neocortex is an object of immense fascination. Human neocortex expansion during evolution has been attributed to an increase in the proliferative capacity of neural progenitor cells during development, particularly basal radial glia (bRG). Despite their evolutionary relevance, the genomic changes driving human-specific bRG biology remain uncharacterized. We used comparative chromatin and transcriptional profiling of neural progenitor cells isolated from gorilla, chimpanzee and human cerebral organoids to identify cis-regulatory elements that have gained activity in humans. Focusing specifically on bRG, we discovered that morphoregulatory enhancer activity and gene expression signatures distinguish human bRG from other great apes. Functional analysis of the morphoregulatory genes FAM107A and CNGA3 in human organoids revealed that these genes are required for the morphological complexity of human bRG. Taken together, our interspecies comparison of basal radial glia suggests that human-specific morphoregulatory signatures characterize neocortex evolution.

neuroscience↗

bioRxiv2025

TGF-β3 Promotes Trophoblast Development via ACSS2-Dependent Permissive Lipid Metabolism

Transforming growth factor-beta (TGF-{beta}) supports the in vitro maintenance of embryonic and trophoblast stem cells. Here, we demonstrated that, in a sheep embryo model, the transition from morula to blastocyst is positively regulated by TGF-{beta}3, primarily through its promotion of trophoblast development. Our results indicate that morulae treated with TGF-{beta}3 develop at a higher rate into blastocysts, characterized by an expanded trophoblast layer marked by CDX-2 expression. In blastocysts, TGF-{beta}3 mediates transcriptional activation of genes involved in cell adhesion and lipid metabolism pathways, leading to remarkable in vitro outgrowth expansion and a substantial increase in trophoblast lipid droplet content. Functional analysis reveal that the positive effects of TGF-{beta}3 are mitigated by inhibition of Acetyl-CoA Synthetase Short-Chain Family Member 2 (ACSS2), a key enzyme upregulated by TGF-{beta}3 and a promoter of de novo lipgenensis. These findings suggest that TGF-{beta}3 modulates lipid metabolism during blastocyst formation and may play a potential role in regulating implantation and placental development.

developmental biology↗

bioRxiv2024

Adducins regulate morphology and fate of neural progenitors during neocortical neurogenesis

The evolutionary expansion of the mammalian neocortex is mediated by an increase in the proliferative capacity of neural progenitor cells. However, the molecular machinery controlling the proliferation of apical and basal progenitors during neocortical development is still poorly understood. Here we show that the three actin-associated morpho-regulatory adducins (ADD1-3), underlie abundance of basal progenitors in developing mouse and ferret neocortex in vivo and in human cortical organoids. Over expression of adducins in embryonic mouse neocortex increases the number of protrusions of basal progenitors, leading to an increase in their proliferative capacity and neuronal output. Conversely, knock-out of ADD1 in human cortical organoids, which also leads to down-regulation of other adducins, results in reduced proliferation of progenitors and aberrant neurogenesis. Hence, we show that adducins underlie proliferation and fate of neural progenitors, which are key cellular features underlying progression of mammalian neurogenesis.

neuroscience↗

bioRxiv2022

Characterization of BoHV-4 ORF45

Bovine herpesvirus 4 (BoHV-4) is a Gammaherpesvirus of the genus Rhadinovirus, his natural host is the bovine whereas the African Buffalo the natural reservoir. Anyhow, BoHV-4 infection is not associated to a specific disease. Genome structure and genes are well conserved in Gammaherpesvirus, and orf45 gene and its product, ORF45, is one of those. BoHV-4 ORF45 has been suggested to be a tegument protein, however, BoHV-4 ORF45 structure and function have not yet been experimentally characterized. In the present study, it is shown that BoHV-4 ORF45, despite its poor homology with other characterized Rhadinovirus ORF45s, is structurally related to Kaposis sarcoma-associated herpesvirus (KSHV), is a phosphoprotein and localizes in the host cell nuclei. Through the generation of an ORF45-null mutant BoHV-4 and its pararevertant, it was possible to demonstrate that ORF45 is essential for BoHV-4 lytic replication and is associated to the viral particles, as for the other characterized Rhadinovirus ORF45s. Finally, the impact of BoHV-4 ORF45 on cellular transcriptome was investigated, an aspect poorly explored or not at all for other Gammaherpesvirus. Many cellular transcriptional pathways were found to be alterate, mainly those involving p90 ribosomal S6 kinase (RSK) and signal-regulated kinase (ERK) complex (RSK/ERK), thus highlighting the authentic character of BoHV-4 ORF45 and paving the way to further investigations.

microbiology↗