We employ RNA-seq of FACS sorted cell populations to identify genes that are enriched in cranial neural crest in relationship to the trunk. Overall design: Transcriptional profiling of delaminating cranial and trunk neural crest subpopulations.
Reprogramming of avian neural crest axial identity and cell fate.
Specimen part, Subject
View SamplesProprioception relies on two main classes of proprioceptive sensory neurons (pSNs). These neurons innervate two distinct peripheral receptors in muscle, muscle spindles (MSs) or Golgi tendon organs (GTOs), and synapse onto different sets of spinal targets, but the molecular basis of their distinct pSN subtype identity remains unknown.
The PDZ-domain protein Whirlin facilitates mechanosensory signaling in mammalian proprioceptors.
Sex, Specimen part
View SamplesMelanocytes within benign human nevi are the paradigm for tumor suppressive senescent cells in a pre-malignant neoplasm. These cells typically contain mutations in either the BRAF or N-RAS oncogene and express markers of senescence, including p16. However, a nevus can contain 10s to 100s of thousands of clonal melanocytes and approximately 20-30% of melanoma are thought to arise in association with a pre-existing nevus. Neither observation is indicative of fail-safe senescence-associated proliferation arrest and tumor suppression. We set out to better understand the status of nevus melanocytes. Proliferation-promoting Wnt target genes, such as cyclin D1 and c-myc, were repressed in oncogene-induced senescent melanocytes in vitro, and repression of Wnt signaling in these cells induced a senescent-like state. In contrast, cyclin D1 and c-myc were expressed in many melanocytes of human benign nevi. Specifically, activated Wnt signalling in nevi correlated inversely with nevus maturation, an established dermatopathological correlate of clinical benignancy. Single cell analyses of lone epidermal melanocytes and nevus melanocytes showed that expression of proliferation-promoting Wnt targets correlates with prior proliferative expansion of p16-expressing nevus melanocytes. In a mouse model, activation of Wnt signaling delayed, but did not bypass, senescence of oncogene-expressing melanocytes, leading to massive accumulation of proliferation-arrested, p16-positive non-malignant melanocytes. We conclude that clonal hyperproliferation of oncogene-expressing melanocytes to form a nevus is facilitated by transient delay of senescence due to activated Wnt signaling. The observation that activation of Wnt signaling correlates inversely with nevus maturation, an indicator of clinical benignancy, supports the notion that persistent destabilization of senescence by Wnt signaling contributes to the malignant potential of nevi. Overall design: We used RNA-Seq to detail the global programme of gene expression in human melanoma cell lines
MLL1 is essential for the senescence-associated secretory phenotype.
Cell line, Subject
View SamplesOncogene-induced senescence (OIS) and therapy-induced senescence (TIS), while tumor-suppressive, also promote procarcinogenic effects by activating the DNA damage response (DDR), which in turn induces inflammation. This inflammatory response prominently includes an array of cytokines known as the senescence-associated secretory phenotype (SASP). Previous observations link the transcription-associated methyltransferase and oncoprotein MLL1 to the DDR, leading us to investigate the role of MLL1 in SASP expression. Our findings reveal direct MLL1 epigenetic control over proproliferative cell cycle genes: MLL1 inhibition represses expression of proproliferative cell cycle regulators required for DNA replication and DDR activation, thus disabling SASP expression. Strikingly, however, these effects of MLL1 inhibition on SASP gene expression do not impair OIS and, furthermore, abolish the ability of the SASP to enhance cancer cell proliferation. More broadly, MLL1 inhibition also reduces “SASP-like” inflammatory gene expression from cancer cells in vitro and in vivo independently of senescence. Taken together, these data demonstrate that MLL1 inhibition may be a powerful and effective strategy for inducing cancerous growth arrest through the direct epigenetic regulation of proliferation-promoting genes and the avoidance of deleterious OIS- or TIS-related tumor secretomes, which can promote both drug resistance and tumor progression. Overall design: This study consists of a single replicate of RNA-seq from oncogene-induced senescent (or control) IMR90 cells in a MLL1 knockdown (or WT) background, for a total of four samples
MLL1 is essential for the senescence-associated secretory phenotype.
No sample metadata fields
View SamplesWe obtained radiographically-localized biopsies during glioma resection surgeries to sample the tumor core and margins from multiple glioma patients. We also procured fresh, non-neoplastic brain tissue specimens from multiple patients having procedures to relieve epilespy symptoms or to place shunts to treat normal pressure hydrocephalus. We then used RNA-Seq to compare expression patterns between geographically distinct regions of gliomas and computational deconvolution to estimate cell type-specific expression patterns in different disease subtypes. Overall design: RNA-Seq analysis in 39 contrast-enhancing glioma core samples, 36 non-enhancing FLAIR glioma margin samples, and 17 non-neoplastic brain tissue samples.
MRI-localized biopsies reveal subtype-specific differences in molecular and cellular composition at the margins of glioblastoma.
No sample metadata fields
View SamplesNon-typhoidal Salmonella (NTS) are among of the most important food-borne pathogens. Recently, a highly invasive multi-drug resistant S. Typhimurium of a distinct multilocus sequence type (MLST), ST313, has emerged across sub-Saharan Africa as a major cause of lethal bacteraemia in children and immunosuppressed adults. Encounters between dendritic cells (DCs) and invading bacteria determine the course of infection but whether or how ST313 might usurp DC mediated defence has not been reported. Here we utilised fluorescently labelled invasive and non-invasive strains of Salmonella combined with single-cell RNA sequencing to study the transcriptomes of individual infected and bystander DCs. The transcriptomes displayed a repertoire of cell instrinsic and extrinsic innate response states that differed between invasive and non-invasive strains. Gene expression heterogeneity was increased in DCs challenged with invasive Salmonella. DCs exposed but not harbouring invasive Salmonella exhibited a hyper-activated profile that likely facilitates trafficking of infected cells and dissemination of internalised intact bacteria. In contrast, invasive Salmonella containing DCs demonstrate reprogramming of trafficking genes required to avoid autophagic destruction. Furthermore, these cells displayed differential expression of tolerogenic IL10 and MARCH1 enabling CD83 mediated adaptive immune evasion. Altogether our data illustrate pathogen cell-to cell variability directed by a Salmonella invasive strain highlighting potential mechanisms of host adaption with implications for dissemination in vivo. Overall design: Single-cell RNA sequencing (SMARTSeq2) of 373 human monocyte derived dendritic cells infected with S. Typhimurium strain LT2 or D23580 or left uninfected
Invasive Salmonella exploits divergent immune evasion strategies in infected and bystander dendritic cell subsets.
Subject, Time
View SamplesNon-typhoidal Salmonella (NTS) are among of the most important food-borne pathogens. Recently, a highly invasive multi-drug resistant S. Typhimurium of a distinct multilocus sequence type (MLST), ST313, has emerged across sub-Saharan Africa as a major cause of lethal bacteraemia in children and immunosuppressed adults. Encounters between dendritic cells (DCs) and invading bacteria determine the course of infection but whether or how ST313 might usurp DC mediated defence has not been reported. Here we utilised fluorescently labelled invasive and non-invasive strains of Salmonella combined with single-cell RNA sequencing to study the transcriptomes of individual infected and bystander DCs. The transcriptomes displayed a repertoire of cell instrinsic and extrinsic innate response states that differed between invasive and non-invasive strains. Gene expression heterogeneity was increased in DCs challenged with invasive Salmonella. DCs exposed but not harbouring invasive Salmonella exhibited a hyper-activated profile that likely facilitates trafficking of infected cells and dissemination of internalised intact bacteria. In contrast, invasive Salmonella containing DCs demonstrate reprogramming of trafficking genes required to avoid autophagic destruction. Furthermore, these cells displayed differential expression of tolerogenic IL10 and MARCH1 enabling CD83 mediated adaptive immune evasion. Altogether our data illustrate pathogen cell-to cell variability directed by a Salmonella invasive strain highlighting potential mechanisms of host adaption with implications for dissemination in vivo. Overall design: RNA-seq of mini-bulks (5000 cells) of human monocyte derived dendritic cells infected with S. Typhimurium strain LT2 or D23580 or left uninfected
Invasive Salmonella exploits divergent immune evasion strategies in infected and bystander dendritic cell subsets.
Subject, Time
View SamplesThe role of diet in the prevention of breast cancer is widely accepted, yet little is known on how early dietary effects mitigate adult cancer risk. Soy consumption is associated with reduced breast cancer risk in women, an effect largely attributed to the soy isoflavone genistein (GEN). We previously showed lower chemically-induced mammary tumor incidence in young adult rats with lifetime dietary intake of soy protein isolate (SPI), a highly refined soy product in infant formula, than in those fed the control diet Casein (CAS). To gain insight into signaling pathways underlying dietary tumor protection, we performed genome-wide expression profiling of mammary epithelial cells from young adult rats lifetime fed CAS, SPI, or supplemental GEN-based diets. We identified mammary epithelial genes regulated by SPI (79 total) and GEN (99 total) using Affymetrix rat 230A GeneChip arrays and found minimal overlap in gene expression patterns. We showed that the regulated transcripts functionally cluster in biochemical pathways involving metabolism, immune response, signal transduction, and ion transport. We confirmed the differential expression of Wnt (Wnt5a, Sfrp2) and Notch (Notch2, Hes1) signaling components by SPI and/or GEN using QPCR. Wnt pathway inhibition by GEN was supported by lower Cyclin D1 immunoreactivity in mammary ductal epithelium of GEN relative to CAS and SPI, despite their comparable levels of membrane-localized E-cadherin and -catenin. Identification of distinct GEN and SPI responsive genes in mammary epithelial cells may define early events contributing to tumor protection by diet relevant to the prevention of breast and other types of cancer.
Expression profiling of rat mammary epithelial cells reveals candidate signaling pathways in dietary protection from mammary tumors.
No sample metadata fields
View SamplesOptically decodable beads link the identity of an analyte or sample to a measurement through an optical barcode, enabling libraries of biomolecules to be captured on beads in solution and decoded by fluorescence. This approach has been foundational to microarray, sequencing, and flow-based expression profiling technologies. We have combined microfluidics with optically decodable beads to link phenotypic analysis of living cells to sequencing. As a proof-of-concept, we applied this to demonstrate an accurate and scalable tool for connecting live cell imaging to single-cell RNA-Seq called Single Cell Optical Phenotyping and Expression (SCOPE-Seq). Overall design: Performed SCOPE-Seq on thousands of cells from two cell lines.
SCOPE-Seq: a scalable technology for linking live cell imaging and single-cell RNA sequencing.
No sample metadata fields
View SamplesRNA-sequencing (RNA-seq) measures RNA abundance in a biological sample but does not provide temporal information about the sequenced RNAs. Metabolic labeling can be used to distinguish newly made RNAs from pre-existing RNAs. Mutations induced from chemical recoding of the hydrogen bonding pattern of the metabolic label can reveal which RNAs are new in the context of a sequencing experiment. These nucleotide recoding strategies have been developed for a single uridine analogue, 4-thiouridine (s4U), limiting the scope of these experiments. Here we report expansion of TimeLapse sequencing (TimeLapse-seq) to the guanosine analogue, 6-thioguanosine (s6G), which can be recoded under RNA-friendly nucleophilic-aromatic substitution conditions to produce adenine analogues (substituted 2-aminoadenosines). We demonstrate the first use of s6G recoding experiments to reveal transcriptome-wide RNA population dynamics. Overall design: Distinguishing newly made from preexising RNA using RNA-sequencing of 6-thioguanosine containing RNA, which was subjected to TimeLapse chemistry to induce G to A mutations in newly-made RNA.
Expanding the Nucleoside Recoding Toolkit: Revealing RNA Population Dynamics with 6-Thioguanosine.
Cell line, Treatment, Subject
View Samples