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Feng, M. Y.

Publications and source records attributed to Feng, M. Y..

4 recordsLinked to original sources

Spatial dynamics of cellular and molecular plasticity in the maternal and postpartum mouse brain

Pregnancy is a critical window for neuroplasticity and maternal mental health, yet our understanding of the molecular and cellular changes underlying this adaptation remains incomplete. Here we profile the female mouse brain in nulliparous, late-pregnant and postpartum states with three single-cell spatial technologies (Slide-tags, MERFISH and Xenium). Together these assays resolve 1.5 million cells in one coronal plane spanning the cortex, striatum, lateral septum and preoptic area. Pregnancy is associated with changes in gene expression in most cell types, beyond the circuits previously established to govern maternal behavior. These changes resolve into three programs that are reproducible across platforms: synaptic pathways increase in neurons as growth and plasticity pathways decrease; immune and angiogenic pathways increase in glia and vascular cells; and cholesterol synthesis decreases as uptake increases across both neurons and glia. Finally, mapping human depression genetics onto these data, we find risk genes concentrated almost entirely in neurons, and this concentration changes with reproductive state in the preoptic area, basal forebrain and ventral striatum. These results place the neurons carrying depression risk among the circuits remodeled during pregnancy, providing a possible cellular substrate for peripartum vulnerability.

genomics↗

HuD controls widespread RNA stability to drive neuronal activity-dependent responses

Neuronal activity shapes brain development and refines synaptic connectivity in part through dynamic changes in gene expression. While activity-regulated transcriptional programs have been extensively characterized, the holistic effects of neuronal activity on the full RNA life cycle remain relatively unexplored. Here, we show that neuronal activity influences multiple stages of RNA metabolism in vitro and in vivo. Among these, RNA stability emerges as a previously underappreciated regulator of gene expression, exerting a stronger influence than transcription on total RNA levels for [~]15% of activity-dependent genes. We go on to profile 3'UTR mRNA motifs that are sufficient to modulate activity-dependent mRNA stability and employ machine learning to identify the neuronal-specific RNA-binding protein HuD as a key regulator of activity-dependent mRNA stabilization. We demonstrate that HuD shapes activity-dependent mRNA abundance of hundreds of transcripts in both soma and distal neuronal processes and that neuronal activity drives the reorganization of HuD-interacting proteins, thereby stabilizing HuD-bound mRNAs and directing them into translationally active granules. Finally, we find that many variants associated with autism spectrum disorder (ASD) and other neurodevelopmental disorders disrupt or promote aberrant activity-dependent changes in mRNA stability. These findings reveal mRNA stability as a widespread mechanism of stimulus-responsive gene regulation in neurons with direct implications for the understanding of neurodevelopmental disorders.

neuroscience↗

Perinatal Brain Injury Triggers Niche-Specific Changes to Cellular Biogeography

Preterm infants are at risk for brain injury and neurodevelopmental impairment due, in part, to white matter injury following chronic hypoxia exposure. However, the precise molecular mechanisms by which perinatal hypoxia disrupts early neurodevelopment are poorly understood. Here, we constructed a brain-wide map of the regenerative response to newborn brain injury using high-resolution imaging-based spatial transcriptomics to analyze over 1.3 million cells in a mouse model of chronic neonatal hypoxia. Additionally, we developed a new method for inferring condition-associated differences in cell type spatial proximity, enabling the identification of niche-specific changes in cellular architecture. We observed hypoxia-associated changes in region-specific cell states, cell type composition, and spatial organization. Importantly, our analysis revealed mechanisms underlying reparative neurogenesis and gliogenesis, while also nominating pathways that may impede circuit rewiring following perinatal hypoxia. Altogether, our work provides a comprehensive description of the molecular response to newborn brain injury.

neuroscience↗

Single-nucleus profiling identifies accelerated oligodendrocyte precursor cell senescence in a mouse model of Down Syndrome

Down Syndrome (DS), the most common genetic cause of intellectual disability, is associated with lifelong cognitive disability. However, the mechanisms by which triplication of human chromosome 21 genes drive neuroinflammation and cognitive dysfunction are poorly understood. Here, using the Ts65Dn mouse model of DS, we performed an integrated single-nucleus RNA and ATAC-seq analysis of the cortex. We identify cell type-specific transcriptional and chromatin-associated changes in the Ts65Dn cortex, including regulators of neuroinflammation, transcription and translation, myelination, and mitochondrial function. We discover enrichment of a senescence-associated transcriptional signature in Ts65Dn oligodendrocyte precursor cells (OPCs) and epigenetic changes consistent with a loss of heterochromatin. We find that senescence is restricted to a subset of cortical OPCs concentrated in deep cortical layers. Treatment of Ts65Dn mice with a senescence-reducing flavonoid rescues cortical OPC proliferation, restores microglial homeostasis, and improves contextual fear memory. Together, these findings suggest that cortical OPC senescence may be an important driver of neuropathology in DS.

neuroscience↗