Biology subjects

Espuny Camacho, I.

Publications and source records attributed to Espuny Camacho, I..

3 recordsLinked to original sources

bioRxiv2026

Untangling mechanisms for cerebellar neural specification using human pluripotent stem cell-derived organoids

The cerebellum is one of the most complex structures of the brain composed of a high diversity of GABAergic and glutamatergic neurons. Whereas cerebellar biogenesis has been extensively studied in the mouse, an in-depth characterization of genes and pathways involved in cerebellar specification and maturation in the humans remains overlooked. Here, we used human pluripotent stem cells (hPSC)-derived cerebellar organoids (CRBOs) to study the temporal biogenesis of neuronal subtypes. Our results show that CRBOs acquire caudal neural tube identity at an early stage followed by a time-dependent expression of mature cerebellar neuronal markers in vitro, mimicking human neurodevelopment. CRBOs show the generation of both cerebellar excitatory and inhibitory neurons and the expression of glial cell markers, suggesting the generation of a high variety of cerebellar cell types in vitro. Further, in vitro CRBOs show expression of cerebellar disease associated genes, such as those related to ataxia. Our results establish CRBOs as a valuable platform to explore the mechanisms of human cerebellar development and related disorders.

neuroscience↗

bioRxiv2024

Ccp1 depletion disrupts network integration of hippocampal parvalbumin interneurons

Post-translational modifications (PTMs) of microtubules (MTs) endow them with specific properties that are essential for key cellular functions, such as axonal transport. Polyglutamylation, a PTM that accumulates in long-lived MTs, has been linked to neurodegeneration in the cerebellum when in excess. While hyperglutamylation of MTs leads to neurodegeneration and disrupts the function of specific neuronal subtypes like Purkinje cells, cortical neurons, and hippocampal excitatory neurons, little is known about its impact on inhibitory interneurons and their functional integration into local networks. In this study, we generated a conditional knockout mouse model to deplete cytosolic carboxypeptidase 1 (Ccp1) in GABAergic neurons, a key MT deglutamylase expressed by hippocampal interneurons. Our findings reveal that the loss of Ccp1 has a profound effect on hippocampal parvalbumin (PV)-expressing interneurons, impairing their axonal transport and reducing their perisomatic inhibition of pyramidal cells (PCs) in the CA2 region of the hippocampus. Research TopicsMolecular Neuroscience, Cell Biology HighlightsO_LIDifferent subtypes of hippocampal interneurons express unique sets of (de)glutamylases and show varying levels of protein posttranslational glutamylation. C_LIO_LIParvalbumin interneurons become hyperglutamylated when Ccp1 activity is lost. C_LIO_LIThe loss of Ccp1 disrupts axonal transport in interneurons and is associated with decreased perisomatic inhibition of hippocampal pyramidal cells in the CA2 region. C_LI

neuroscience↗

bioRxiv2022

Brain regional identity and cell type specificity landscape of human cortical organoid models

In vitro models of corticogenesis using mouse and human pluripotent stem cells (PSC) have greatly improved our understanding of human brain development and disease. Among these, 3D cortical organoid systems are able to recapitulate some aspects of in vivo cytoarchitecture of the developing cortex. Here, we tested three cortical organoid protocols for brain regional identity, cell type-specificity and neuronal maturation. Overall all protocols gave rise to organoids that displayed a time-dependent expression of neuronal maturation genes such as those involved in the establishment of synapses and neuronal function. We showed that three months old cortical organoids showed a pattern of gene expression that resembled late human embryonic cortex. Comparatively, directed differentiation methods without WNT activation gave rise to the highest degree of cortical regional identity in brain organoids. Whereas, default "intrinsic" brain organoid differentiation produced the broadest range of cell types such as neurons, astrocytes and hematopoietic-lineage derived microglia cells of the brain. These results suggest that cortical organoid models produce diverse outcomes in terms of brain regional identity and cell type specificity and emphasize the importance of selecting the correct model for the right application.

neuroscience↗