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Vo, D.

Publications and source records attributed to Vo, D..

5 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↗

The Innexin 7 gap junction protein contributes to synchronized activity in the Drosophila antennal lobe and regulates olfactory function

In the mammalian olfactory bulb (OB), gap junctions coordinate synchronous activity among mitral and tufted cells to process olfactory information. In insects, gap junctions are also present in the Antennal Lobe (AL), a structure homologous to the mammalian OB. The invertebrate gap junction protein ShakB contributes to electrical synapses between AL Projections Neurons (PNs) in Drosophila. Other gap junction proteins, including Innexin 7 (Inx7), are also expressed in the Drosophila AL, but little is known about their contribution to intercellular communication during olfactory information processing. Here we report spontaneous calcium transients in PNs grown in cell culture that are highly synchronous when these neurons are physically connected. RNAi-mediated knock down of Inx7 in cultured PNs blocks calcium transient neuronal synchronization. In vivo, downregulation of Inx7 in the AL impairs both vinegar-induced electrophysiological calcium responses and behavioral responses to this appetitive stimulus. These results demonstrate that Inx7-encoded gap junctions functionally coordinate PN activity and modulate olfactory information processing in the adult Drosophila AL.

neuroscience↗

SPT6 loss Permits the Transdifferentiation of Keratinocytes into anIntestinal Fate that Recapitulates Barretts Metaplasia

Transient depletion of the transcription elongation factor SPT6 in the keratinocyte has been recently shown to inhibit epidermal differentiation and stratification; instead, they transdifferentiate into a gut-like lineage. We show here that this phenomenon of transdifferentiation recapitulates Barretts metaplasia, the only human pathophysiologic condition in which a stratified squamous epithelium that is injured due to chronic acid reflux is trans-committed into an intestinal fate. The evidence we present here not only lend support to the notion that the keratinocytes are the cell of origin of Barretts metaplasia, but also provide mechanistic insights linking transient acid exposure, downregulation of SPT6, stalled transcription of the master regulator of epidermal fate TP63, loss of epidermal fate and metaplastic progression. Because Barretts metaplasia in the esophagus (BE) is a pre-neoplastic condition with no preclinical human models, these findings have a profound impact on the modeling Barretts metaplasia-in-a-dish. GRAPHIC ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=192 HEIGHT=200 SRC="FIGDIR/small/442930v2_ufig1.gif" ALT="Figure 1"> View larger version (58K): org.highwire.dtl.DTLVardef@8ce08aorg.highwire.dtl.DTLVardef@e98c83org.highwire.dtl.DTLVardef@107f521org.highwire.dtl.DTLVardef@16e7523_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSO_LIKeratinocytes transdifferentiate into the gut lineage upon depletion of SPT6 C_LIO_LISuch transdifferentiation recapitulates Barretts metaplasia, not the healthy gut C_LIO_LIAcid downregulates SPT6, which derails the expression and functions of TP63 C_LIO_LISuch downregulation precedes the metaplasia-dysplasia-neoplasia cascade C_LI

cell biology↗

Immune cell networks uncover candidate biomarkers of cancer immunotherapy response

Therapeutic activation of antitumour immunity by immune checkpoint inhibitors (ICIs) is a significant advance in cancer medicine, not least due to the prospect of long-term remission. However, many patients are unresponsive to ICI therapy and may experience serious side effects; companion biomarkers are urgently needed to help inform ICI prescribing decisions. We present the IMMUNETS networks of gene coregulation in five key immune cell types, and application to interrogate control of nivolumab response in advanced melanoma cohorts. Results evidence a role for each of the IMMUNETS cell types in ICI response and in driving tumour clearance with independent cohorts from TCGA. As expected, immune hot status, including T cell proliferation, confers good response to first line ICI therapy. Genes regulated in NK, dendritic and B cells are the most prominent discriminators of nivolumab response in patients that had previously progressed on another ICI. Multivariate analysis controlling for tumour stage and age highlights B cell genes as candidate prognostic biomarkers. IMMUNETS provide a resource for network biology, enabling context-specific analysis of immune components in orthogonal datasets. Overall, our results illuminate the relationship between the tumour microenvironment and clinical trajectories, with potential implications for precision medicine.

systems biology↗

The Anatomical Tracings of Lesions After Stroke (ATLAS) Dataset - Release 1.1

Stroke is the leading cause of adult disability worldwide, with up to two-thirds of individuals experiencing long-term disabilities. Large-scale neuroimaging studies have shown promise in identifying robust biomarkers (e.g., measures of brain structure) of long-term stroke recovery following rehabilitation. However, analyzing large rehabilitation-related datasets is problematic due to barriers in accurate stroke lesion segmentation. Manually-traced lesions are currently the gold standard for lesion segmentation on T1-weighted MRIs, but are labor intensive and require anatomical expertise. While algorithms have been developed to automate this process, the results often lack accuracy. Newer algorithms that employ machine-learning techniques are promising, yet these require large training datasets to optimize performance. Here we present ATLAS (Anatomical Tracings of Lesions After Stroke), an open-source dataset of 304 T1-weighted MRIs with manually segmented lesions and metadata. This large, diverse dataset can be used to train and test lesion segmentation algorithms and provides a standardized dataset for comparing the performance of different segmentation methods. We hope ATLAS release 1.1 will be a useful resource to assess and improve the accuracy of current lesion segmentation methods.

neuroscience↗