Project description:Loss of UBE3A expression, a gene regulated by genomic imprinting, causes Angelman syndrome (AS), a rare neurodevelopmental disorder. The UBE3A gene encodes an E3 ubiquitin ligase with three known protein isoforms in humans. Studies in mouse suggest that the human isoforms may have differences in localization and neuronal function. A recent case study reported mild AS phenotypes in individuals lacking one specific isoform. Here we have used CRISPR/Cas9 to generate isogenic human embryonic stem cells (hESCs) that lack the individual protein isoforms. We demonstrate that isoform 1 accounts for the majority of UBE3A protein in hESCs and neurons. We also show that UBE3A predominantly localizes to the cytoplasm in both wild type and isoform-null cells. Finally, we show that neurons lacking isoform 1 display a less severe electrophysiological AS phenotype.
Project description:We identified the abundance of isoforms of miRNAs encoded by human adenovirus 5 in total cytoplasmic RNA fractions of infected cells as well as in fractions containing the purified RNA-induced silencing complex (RISC).
Project description:Long noncoding RNAs (lncRNAs) have emerged as key players in different cellular processes and are required for diverse functions in vivo. However, fundamental aspects of lncRNA biology remain poorly characterized, including their subcellular localization, abundance and variation at a single cell resolution. Here, we used single molecule, single-cell RNA fluorescence in situ hybridization (RNA FISH) to survey 61 lncRNAs, chosen by properties such as conservation, tissue specific expression, and expression abundance, and to catalog their abundance and cellular localization patterns in three human cell types. Our lncRNAs displayed diverse sub-cellular localization patterns ranging from strictly nuclear localization to almost exclusive cytoplasmic localization, with the majority localized primarily in the nucleus. The low abundance of these lncRNAs as measured in bulk cell populations cannot be explained by high expression in a small subset of 'jackpot' cells. Simultaneous analysis of lncRNAs and mRNAs from corresponding divergently transcribed loci showed that divergent lncRNAs do not present a distinct localization pattern and are not always co-regulated with their neighbor. Overall, our study highlights important differences and similarities between lncRNAs and mRNAs. The rich set of localization patterns we observe are consistent with a broad range of potential functions for lncRNA, and assists in hypothesis generation for mechanistic studies. Here we provide the RNA-Seq expression matrix, as well as RNA-Seq raw data, which we used for comparison with RNA FISH molecule counts. We estimate FPKM of coding genes and lncRNAs across HeLa, human lung fibroblasts and human foreskin. This study includes data from human foreskin fibroblasts (hFF), human lung fibroblasts (hLF), and HeLa cells. An hFF sample (GSM1376178) and the hLF samples (GSM1376175-GSM1376177) were previously submitted and are available in GSE30554 as GSM759893 and GSM759890-GSM759892, respectively. The HeLa samples (GSM591670-GSM591671) were previously submitted and are available in GSE23316. The complete dataset representing: (1) the hFF Samples, including the re-analysis of the hFF Sample from GSE30554, (2) the re-analysis of the hLF Samples from GSE30554, and (3) the re-analysis of the HeLa Samples from GSE23316, is linked below as a supplementary file.
Project description:Long noncoding RNAs (lncRNAs) have emerged as key players in different cellular processes and are required for diverse functions in vivo. However, fundamental aspects of lncRNA biology remain poorly characterized, including their subcellular localization, abundance and variation at a single cell resolution. Here, we used single molecule, single-cell RNA fluorescence in situ hybridization (RNA FISH) to survey 61 lncRNAs, chosen by properties such as conservation, tissue specific expression, and expression abundance, and to catalog their abundance and cellular localization patterns in three human cell types. Our lncRNAs displayed diverse sub-cellular localization patterns ranging from strictly nuclear localization to almost exclusive cytoplasmic localization, with the majority localized primarily in the nucleus. The low abundance of these lncRNAs as measured in bulk cell populations cannot be explained by high expression in a small subset of 'jackpot' cells. Simultaneous analysis of lncRNAs and mRNAs from corresponding divergently transcribed loci showed that divergent lncRNAs do not present a distinct localization pattern and are not always co-regulated with their neighbor. Overall, our study highlights important differences and similarities between lncRNAs and mRNAs. The rich set of localization patterns we observe are consistent with a broad range of potential functions for lncRNA, and assists in hypothesis generation for mechanistic studies. Here we provide the RNA-Seq expression matrix, as well as RNA-Seq raw data, which we used for comparison with RNA FISH molecule counts.
Project description:Angelman syndrome is a neurodevelopmental disorder caused by (epi)genetic lesions of maternal UBE3A. Research has focused largely on the role of UBE3A in neurons due to its imprinting in that cell type. Yet, evidence suggests there may be broader neurodevelopmental impacts of UBE3A dysregulation. Human cerebral organoids can investigate these understudied aspects of UBE3A as they recapitulate diverse cell types of the developing human brain. We performed single-cell RNA-sequencing on organoids to reveal the effects of UBE3A disruption on cell type-specific transcriptomic alterations and compositions. In the absence of UBE3A, progenitor proliferation and structures were disrupted while organoid composition shifted away from proliferative cell types. We observed impacts on non-neuronal cells including choroid plexus enrichment. Furthermore, EMX1+ cortical progenitors were negatively impacted, disrupting corticogenesis, and potentially delaying neuron maturation. This work reveals novel impacts of UBE3A on understudied cell types and related neurodevelopmental processes and elucidates potential new therapeutic targets.
Project description:The dysregulation of genes in neurodevelopmental disorders that lead to social and cognitive phenotypes is a complex, multilayered process involving both genetics and epigenetics. Parent-of-origin effects of deletion and duplication of the 15q11-q13 locus leading to Angelman, Prader-Willi, and Dup15q syndromes are due to imprinted genes, including UBE3A, which is maternally expressed exclusively in neurons. UBE3A encodes a ubiquitin E3 ligase protein with multiple downstream targets, including RING1B, which in turn monoubiquitinates histone variant H2A.Z. To understand the impact of neuronal UBE3A levels on epigenome-wide marks of DNA methylation, histone variant H2A.Z positioning, active H3K4me3 promoter marks, and gene expression, we took a multi-layered genomics approach. We performed an siRNA knockdown of UBE3A in two human neuroblastoma cell lines, including parental SH-SY5Y and the SH(15M) model of Dup15q. Genes differentially methylated across cells with differing UBE3A levels were enriched for functions in gene regulation, DNA binding, and brain morphology. Importantly, we found that altering UBE3A levels had a profound epigenetic effect on the methylation levels of up to half of known imprinted genes. Genes with differential H2A.Z peaks in SH(15M) compared to SH-SY5Y were enriched for ubiquitin and protease functions and associated with autism, hypoactivity, and energy expenditure. Together, these results support a genome-wide epigenetic consequence of altered UBE3A levels in neurons and suggest that UBE3A regulates an imprinted gene network involving DNA methylation patterning and H2A.Z deposition.
Project description:This strand-specific array is performed to characterize expression features of Ube3a-ATS, including its imprinting status, its exon-intron structure, its transcriptional initiation and termination site as well as its polyadenylation status. The array contains reverse-complementary probes detecting transcripts from both strands and therefore we are able to pick up signal from both Ube3a sense and antisense. By comparing wild-type with various mutants, and total RNA with polyA RNA, we concluded that Ube3a-ATS is a paternally imprinted gene covering the whole gene body of Ube3a in the antisense orientation. It does not have an obvious exon-intron structure. Its transcription initiates at Snrpn major promoter and terminates ~40kb upstream of Ube3a transcriptional start site. Total RNA from Snrpn-Ube3a maternal deletion mutant (del s-u/+), its wild-type littermate, paternal deletion mutant and its wildtype littermate were analyzed. Mutant mice with S-U maternal deletion and Snrpn promoter paternal deleiton which leads to depletion of Ube3a-ATS (del s-u/0.9 and del s-u/4.8) were also analyzed. polyA RNA was purified from the sample 2 and sample 4. All eight samples were hybridized to the custom 8X60k Agilent CGH array.
Project description:This strand-specific array is performed to characterize expression features of Ube3a-ATS, including its imprinting status, its exon-intron structure, its transcriptional initiation and termination site as well as its polyadenylation status. The array contains reverse-complementary probes detecting transcripts from both strands and therefore we are able to pick up signal from both Ube3a sense and antisense. By comparing wild-type with various mutants, and total RNA with polyA RNA, we concluded that Ube3a-ATS is a paternally imprinted gene covering the whole gene body of Ube3a in the antisense orientation. It does not have an obvious exon-intron structure. Its transcription initiates at Snrpn major promoter and terminates ~40kb upstream of Ube3a transcriptional start site.
Project description:The thiazide-sensitive NaCl cotransporter (NCC) is an important pharmacological target in the treatment of hypertension. Human SLC12A3 gene encoding NCC gives rise to three isoforms. Only the isoform 3 has been extensively investigated. The goal of the present study was, therefore, to determine the abundance and localization of NCC1 and NCC2 in comparison to NCC3 in the human kidney as well as their functional properties in physiological and pathological conditions. To this end, the presence of NCC1, NCC2, and NCC3 in the human urinary exosomes was assessed by mass spectrometric analysis.