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de la Torre-Ubieta, L.

Publications and source records attributed to de la Torre-Ubieta, L..

10 recordsLinked to original sources

scRBP infers cell-specific RNA-binding protein regulons from single-cell transcriptomes at gene and isoform resolution

Single-cell regulatory network inference remains dominated by transcription factors, despite RNA-binding proteins (RBPs) orchestrating major aspects of transcriptional regulation. We present scRBP, a framework that infers motif-supported RBP regulons from short- and long-read single-cell transcriptomes at gene and isoform resolution, resolves targets by transcript region (5'UTR, CDS, intron, 3'UTR), scores regulon activity in individual cells, and tests common- and rare-variant association against matched empirical nulls. From 20,746 motifs for 616 RBPs, scRBP recovered experimentally defined targets across 223 ENCODE eCLIP datasets at gene and isoform level. Across 30 tissues, transcript-region preferences separated 3'UTR-associated stability factors from intron-dominant splicing regulators. In published genome-scale CRISPRi Perturb-seq data, scRBP-inferred targets were over-represented among genes responding to RBP knockdown (1.4-2.5-fold across 161 RBPs; FDR<2x10-4). Across 6.2 million cells and 50 traits, scRBP prioritized cell-specific post-transcriptional programs linking human genetic risk to development and disease.

genetics↗

Autism genes converge on three functional programs organized by neuronal subclass, developmental timing, and cortical patterning

Our companion sequencing study uncovered 253 genes robustly associated with autism spectrum disorder (ASD), yet the biological programs they impact, and the cellular, developmental, and spatial contexts in which they converge, remain unresolved. Here we systematically contextualize genes associated with ASD across neurodevelopment and cortical areas, integrating developmental single-cell and spatial atlases with gene- and isoform co-expression, regulatory, proteomic, and synaptic networks. Genetic burden concentrates within temporally-resolved neuronal subclasses: newborn excitatory neurons, immature interneurons, and maturing intratelencephalic lineages. Genes associated with ASD converge on three functional programs--gene regulation, neuronal morphogenesis, and synaptic transmembrane signaling machinery--resolved from 28 ASD-associated networks, several of which are directly regulated by ASD genes including MEF2C, SOX11, and FOXP2. These programs are spatially patterned, with risk genes exhibiting an increasing anterior-to-posterior cortical expression gradient, anchored in the primary visual cortex and driven by excitatory neuron gene-regulatory programs. Finally, ASD risk genes associated with more severe developmental phenotypes show broader excitatory neuron enrichment and less interneuron involvement. Together, these findings anchor ASD genetic vulnerability to specific neurodevelopmental lineages, epochs, and molecular substrates, and delineate the features that distinguish ASD from comorbidities with broader developmental impacts.

genomics↗

A single cell multi-omic analysis identifies molecular and gene-regulatory mechanisms dysregulated in the developing Down syndrome neocortex

Down syndrome is the most common genetic cause of intellectual disability, presenting with cognitive, learning, memory, and language deficits. The cellular and molecular mechanisms driving this disorder remain unclear, limited by a lack of systematic studies in the developing human brain. Here, we leveraged single-nucleus multi-omics to profile the mid-gestation neocortex in a cohort of 26 donors. We observed a reduction in neural progenitors and corticothalamic neurons and concomitant increase of intratelencephalic neurons, accompanied by accelerated time to neuronal specification. We uncovered widespread changes in gene expression, chromatin accessibility and cell interaction networks impacting neurogenesis, specification and maturation and gene-regulatory networks directing these processes, including those downstream of transcription factors encoded in chromosome 21. Finally, we identified cell-specific molecular pathways shared with other neurodevelopmental disorders as well as heritability enrichment of GWAS signals in altered chromatin. Together, our data revealed a cascade of molecular dysregulation outlining the earliest steps in Down syndrome, providing a foundation for future therapeutic targets.

genomics↗

KAT6A mutations drive transcriptional dysregulation of cell cycle and Autism risk genes in an Arboleda-Tham Syndrome cerebral organoid model

Arboleda-Tham Syndrome (ARTHS, OMIM#616268) is a rare neurodevelopmental disorder caused by de novo mutations in KAT6A. Individuals with ARTHS typically exhibit varying degrees of intellectual disability, speech and language deficits and clinical manifestations across multiple systems that lead to abnormal: vision, craniofacial features, cardiac morphology, and gastrointestinal function. To gain insight into the potential neuropathological mechanisms underlying ARTHS, we investigate how KAT6A mutations disrupt in vitro brain development using induced pluripotent stem cells (iPSCs) and cerebral organoids (COs) derived from ARTHS patients harboring KAT6A nonsense mutations. In this study, we conducted comprehensive transcriptomic profiling by performing time-course experiments and generating short-read and long-read RNA sequencing (RNA-seq) data from undifferentiated iPSCs and COs at 15 and 25 days of neural differentiation. Our analysis revealed abnormal expression of 235 genes in ARTHS across all three timepoints examined. Notably, we observed persistent dysregulation of genes such as CTSF, ZNF229, PCDHB12, and PAK3. Additionally, we found a consistent enrichment of PTBP1-target genes among the upregulated genes in ARTHS at all three stages assessed by RNA-seq. During neural differentiation, we identified 980 genes that consistently display aberrant transcription in ARTHS at both CO stages. These genes are enriched for genes involved in cell fate determination through modulation of cell-cycle dynamics (e.g. E2F family) and cell-adhesion molecules (e.g. PCDH genes). Our findings indicate that ARTHS COs exhibit slower downregulation of pluripotency and cell cycle genes compared to controls and that this delay led to an overrepresentation of cycling human neural progenitor markers during neural differentiation in ARTHS. Finally, matching the variable neurodevelopment phenotypes in ARTHS, we discovered that the aberrantly expressed genes in ARTHS are enriched for genes associated with Autism Spectrum Disorder and Epilepsy, with a subset showing isoform-specific dysregulation. Strikingly, the same PTBP1-target genes were enriched amongst the genes that display differential isoform usage in ARTHS. For the first time, we demonstrate that KAT6A mutations lead to a delay in repressing pluripotency and cell cycle genes during neural differentiation, suggesting that prolonged activation of these gene networks disrupts the temporal dynamics of human brain development in ARTHS.

genetics↗

MicroRNA-eQTLs in the developing human neocortex link miR-4707-3p expression to brain size

Expression quantitative trait loci (eQTL) data have proven important for linking non-coding loci to protein-coding genes. But eQTL studies rarely measure microRNAs (miRNAs), small non-coding RNAs known to play a role in human brain development and neurogenesis. Here, we performed small-RNA sequencing across 212 mid-gestation human neocortical tissue samples, measured 907 expressed miRNAs, discovering 111 of which were novel, and identified 85 local-miRNA-eQTLs. Colocalization of miRNA-eQTLs with GWAS summary statistics yielded one robust colocalization of miR-4707-3p expression with educational attainment and brain size phenotypes, where the miRNA expression increasing allele was associated with decreased brain size. Exogenous expression of miR-4707-3p in primary human neural progenitor cells decreased expression of predicted targets and increased cell proliferation, indicating miR-4707-3p modulates progenitor gene regulation and cell fate decisions. Integrating miRNA-eQTLs with existing GWAS yielded evidence of a miRNA that may influence human brain size and function via modulation of neocortical brain development.

genetics↗

Genetic influences on cell type specific gene expression and splicing during neurogenesis elucidate regulatory mechanisms of brain traits

Interpretation of the function of non-coding risk loci for neuropsychiatric disorders and brain-relevant traits via gene expression and alternative splicing is generally performed in bulk post-mortem adult tissue. However, genetic risk loci are enriched in regulatory elements active during neocortical differentiation, and regulatory effects of risk variants may be masked by heterogeneity in bulk tissue. Here, we map expression quantitative trait loci (eQTLs), splicing QTLs (sQTLs), and allele specific expression in primary human neural progenitors (n=85) and their sorted neuronal progeny (n=74), identifying numerous loci not detected in either bulk developing cortical wall or adult cortex. Using colocalization and genetic imputation via transcriptome wide association, we uncover cell-type specific regulatory mechanisms underlying risk for brain-relevant traits that are active during neocortical differentiation. Specifically, we identified a progenitor-specific eQTL for CENPW co-localized with common variant associations of cortical area and educational attainment.

genetics↗

Cell-type specific effects of genetic variation on chromatin accessibility during human neuronal differentiation

Common genetic risk for neuropsychiatric disorders is enriched in regulatory elements active during cortical neurogenesis. However, the mechanisms mediating the effects of genetic variants on gene regulation are poorly understood. To determine the functional impact of common genetic variation on the non-coding genome longitudinally during human cortical development, we performed a chromatin accessibility quantitative trait loci (caQTL) analysis in neural progenitor cells and their differentiated neuronal progeny from 92 donors. We identified 8,111 caQTLs in progenitors and 3,676 caQTLs in neurons, with highly temporal, cell-type specific effects. A subset ([~]20%) of caQTLs were also associated with changes in gene expression. Motif-disrupting alleles of transcriptional activators generally led to decreases in chromatin accessibility, whereas motif-disrupting alleles of repressors led to increases in chromatin accessibility. By integrating cell-type specific caQTLs and brain-relevant genome-wide association data, we were able to fine-map loci and identify regulatory mechanisms underlying non-coding neuropsychiatric disorder risk variants. HighlightsO_LIGenetic variation alters chromatin architecture during human cortical development C_LIO_LIGenetic effects on chromatin accessibility are highly cell-type specific C_LIO_LIAlleles disrupting TF motifs generally decrease accessibility, except for repressors C_LIO_LIcaQTLs facilitate fine-mapping and inference of regulatory mechanisms of GWAS loci C_LI

genetics↗

Transcriptomic and Cellular Decoding of Regional Brain Vulnerability to Neurodevelopmental Disorders

Neurodevelopmental disorders are highly heritable and associated with spatially-selective disruptions of brain anatomy. The logic that translates genetic risks into spatially patterned brain vulnerabilities remains unclear but is a fundamental question in disease pathogenesis. Here, we approach this question by integrating (i) in vivo neuroimaging data from patient subgroups with known causal genomic copy number variations (CNVs), and (ii) bulk and single-cell gene expression data from healthy cortex. First, for each of six different CNV disorders, we show that spatial patterns of cortical anatomy change in youth are correlated with spatial patterns of expression for CNV region genes in bulk cortical tissue from typically-developing adults. Next, by transforming normative bulk-tissue cortical expression data into cell-type expression maps, we further link each disorders anatomical change map to specific cell classes and specific CNV-region genes that these cells express. Finally, we establish convergent validity of this "transcriptional vulnerability model" by inter-relating patient neuroimaging data with measures of altered gene expression in both brain and blood-derived patient tissue. Our work clarifies general biological principles that govern the mapping of genetic risks onto regional brain disruption in neurodevelopmental disorders. We present new methods that can harness these principles to screen for potential cellular and molecular determinants of disease from readily available patient neuroimaging data.

neuroscience↗

Genetic control of gene expression and splicing in the developing human brain

Most genetic risk for human diseases lies within non-coding regions of the genome, which is predicted to regulate gene expression, often in a tissue and stage specific manner. This has motivated building of extensive eQTL resources to understand how human allelic variation affects gene expression and splicing throughout the body, focusing primarily on adult tissue. Given the importance of regulatory pathways during brain development, we characterize the genetic control of the developing human cerebral cortical transcriptome, including expression and splicing, in 201 mid-gestational human brains, to understand how common allelic variation affects gene regulation during development. We leverage expression and splice quantitative trait loci to identify genes and isoforms relevant to neuropsychiatric disorders and brain volume. These findings demonstrate genetic mechanisms by which early developmental events have a striking and widespread influence on adult anatomical and behavioral phenotypes, as well as the evolution of the human cerebral cortex.\n\nHighlightsO_LIGenome wide map of human fetal brain eQTLs and sQTLs provides a new view of genetic control of expression and splicing.\nC_LIO_LIThere is substantial contrast between genetic control of transcript regulation in mature versus developing brain.\nC_LIO_LIWe identify novel regulatory regions specific to fetal brain development.\nC_LIO_LIIntegration of eQTLs and GWAS reveals specific relationships between expression and disease risk for neuropsychiatric diseases and relevant human brain phenotypes.\nC_LI

neuroscience↗

A single cell transcriptomic analysis of human neocortical development

Defining the number, proportion, or lineage of distinct cell types in the developing human brain is an important goal of modern brain research. We defined single cell transcriptomic profiles for 40,000 cells at mid-gestation to identify cell types in the developing human neocortex. We define expression profiles corresponding to all known major cell types at this developmental period and identify multiple transcription factors and co-factors expressed in specific cell types, providing an unprecedented resource for understanding human neocortical development including the first single-cell characterization of human subplate neurons. We characterize major developmental trajectories during early neurogenesis, showing that cell type differentiation occurs on a continuum that involves transitions that tie cell cycle progression with early cell fate decisions. We use these data to deconvolute regulatory networks and map neuropsychiatric disease genes to specific cell types, implicating dysregulation of specific cell types, as the mechanistic underpinnings of several neurodevelopmental disorders. Together these results provide an extensive catalog of cell types in human neocortex and extend our understanding of early cortical development, human brain evolution and the cellular basis of neuropsychiatric disease.\n\nOne Sentence SummaryComprehensive single cell transcriptomes in developing human cortex inform models of cell diversity, differentiation and disease risk.

neuroscience↗