In order to determine the regulators of outer hair cell postnatal maturation, we utilized the RiboTag mouse model to perform a detailed transcriptomic analysis of outer hair cells at five postnatal developmental time points: P8, P14, P28, 6 weeks (6wk) and 10 weeks (10wk). This analysis resulted in consistent enrichment of outer hair cell expressed genes in the immunoprecipitated RNA compared to whole cochlear input RNA from each time point. Using transcription factor binding motif prediction on a set of defined outer hair cell enriched genes, we further use this dataset to identify the helios transcription factor as a regulator of the postnatal outer hair cell transcriptome. Overall design: Examination of the outer hair cell translatome by outer hair cell expressed HA-tagged ribosomal immunoprecipitation at 5 postnatal timepoints (P8, P14, P21, 6wk and 10wk). Immunoprecipitated samples were compared to input cochlear RNA controls in independent biological duplicates or triplicates.
Helios is a key transcriptional regulator of outer hair cell maturation.
Specimen part, Subject
View SamplesSensorineural hearing loss affects the majority of the elderly population. Mammalian hair cells (HC) do not regenerate and current stem cell and gene delivery protocols result only in immature hair cells like-cells. For this reason, characterization of the transcriptional cascades that lead to development and survival of inner ear HC is essential for designing molecular-based treatments for deafness. We employed a cell type-specific approach to analyze the transcriptomes of the mouse early postnatal auditory and vestibular sensory epithelia and of hair cells derived from zebrafish model. Overall design: Murine auditory and vestibular epithelia were separated into hair-cells (HCs) and epithelial non-sensory cells (ENSCs) by flow cytometry. Gene expression levels were recorded in independent triplicates from the sorted cells using RNA-seq
RFX transcription factors are essential for hearing in mice.
No sample metadata fields
View SamplesSensorineural hearing loss affects the majority of the elderly population. Mammalian hair cells (HC) do not regenerate and current stem cell and gene delivery protocols result only in immature hair cells like-cells. For this reason, characterization of the transcriptional cascades that lead to development and survival of inner ear HC is essential for designing molecular-based treatments for deafness. We employed a cell type-specific approach to analyze the transcriptomes of the mouse early postnatal auditory and vestibular sensory epithelia and of hair cells derived from zebrafish model. Overall design: We utilized the ppv3b:GFP transgenic zebrafish, which express GFP predominantly in HC. We sorted GFP-positive and negative cells from 5 day post fertilization (dpf) larvae using flow cytometry, and profiled their transcriptomes using RNA-seq
RFX transcription factors are essential for hearing in mice.
No sample metadata fields
View SamplesIn order to determine the transcriptional effect of Ikzf2 overexpression in mammalian auditory hair cells, mouse cochleae were transfected with either a control GFP or a Ikzf2 virus between postnatal day 1 and 3 (P1-3) and then harvested for single cell gene expression profiling at postnatal day 8 (P8) on the 10X Genomics Single Cell 3' v2 platform. Overall design: Dataset is composed of two separate single cell RNA-Seq samples captured on the 10X Genomics Chromium platform with the Single Cell 3' Solution v2 chemistry. Viral GFP- (control) or Ikzf2-transfected cochleae were harvested and single cell suspensions prepared from transgenic mice expressing tdTomato in hair cells. Hair cells expressing tdTomato were enriched by flow sorting and then captured on the Chromium system in parellel. Library preparation and sequencing was performed as defined by the 10X Genomics Single Cell 3' Solution v2 protocol.
Helios is a key transcriptional regulator of outer hair cell maturation.
Specimen part, Cell line, Treatment, Subject
View SamplesThe importance of the role of microRNAs in gene expression and disease is well recognized. However, what is less appreciated is that almost half of miRNA genes are organized in polycistronic clusters and are therefore co-expressed. The mir-11~998 cluster consists of two miRNAs, miR-11 and miR-998. Here, we describe a novel layer of regulation that links the processing and expression of miR-998 to the presence of the mir-11 gene. We show that the presence of mir-11 in the pri-miRNA is required for processing by Drosha, and deletion of mir-11 prevents the expression of miR-998. Replacing mir-11 with an unrelated miRNA rescued miR-998 expression in vivo and in vitro, as did expressing miR-998 from a shorter, more canonical miRNA scaffold. The embedded regulation of miR-998 is functionally important because unchecked miR-998 expression in the absence of miR-11 resulted in highly penetrant pleiotropic developmental defects. We further show that this novel regulation of expression of miRNAs within a cluster is not limited to the mir-11~998 cluster and likely reflects the more general cis-regulation of expression of individual miRNAs. Thus, our results reveal a novel layer of regulation within miRNA clusters that tempers the functions of the individual miRNAs. Unlinking their expression has the potential to change the expression of multiple miRNA targets and shift biological response. Overall design: RNA was extracted from Drosophila third instar larval eye discs of animals grown in standard conditions; Illumina HiSeq2000 Next Gen RNA Sequencing was performed, and differential expression of genes was assessed in wild-type vs unchecked miR-998 expression
Novel regulation and functional interaction of polycistronic miRNAs.
Specimen part, Subject
View SamplesExpression of dE2F1 induces proliferation and apoptosis. We sought to perform an unbiased analysis of the effect of co-expression of miR-11
mir-11 limits the proapoptotic function of its host gene, dE2f1.
Specimen part
View SamplesThird instar larval eye discs provide an in vivo model for cell cycle exit studies. Posterior to the Second Mitotic Wave proliferation is absent in a wild type eye disc. Inactivating mutations in tumor suppressor-like genes can lead to genome wide changes in gene expression that allow for inappropriate bypass of cell cycle exit signals posterior to the Second Mitotic Wave.
Cooperation between dE2F1 and Yki/Sd defines a distinct transcriptional program necessary to bypass cell cycle exit.
Specimen part
View SamplesWe used microarrays to identify genes that are differentially expressed in the absence of miR-998 expression.
An intronic microRNA links Rb/E2F and EGFR signaling.
Specimen part
View SamplesWe characterized the Drosophila third instar eye disc using single cell RNA-seq and labelled the multiple cell populations. The results identified a novel transcriptional switch in photoreceptors relating to axonal projections. We then performed single cell RNA-seq on rbf (Rb) mutants and compared the results to the WT cell populations. This identified a specific cell population only in the Rb mutant tissue. This cell population has an upregulation of HIF1A and glycolitic genes such as Aldolase and Lactate dehydrogenase. As a result these cells produce lactate and undergo apoptosis. We also show this process to be directly regulated by E2F/Dp. The paper uncovers a novel metabolic aspect of Rb/E2F dependent apoptosis. Overall design: examining WT and Rb mutants third instar eye disc using single cell RNA-seq
Single cell RNA-sequencing identifies a metabolic aspect of apoptosis in Rbf mutant.
Specimen part, Subject
View SamplesApoptosis is an important process to eliminate cells from tissue which have incurred irreparable DNA damage. While dE2F1/dDP complexes respond to such damage by transcriptionally activating apoptotic genes, previous data suggests that activation of the previously characterized apoptotic target genes of dE2F1/dDP alone may not be the only gene regulation important for gamma irradiation-induced apoptosis. Here we report that following irradiation in dDP mutant 3rd instar larval eye imaginal discs, many genes important for oxidative phosphorylation are down-regulated, which are not down-regulated following irradiation in wild type eye discs.
Loss of dE2F compromises mitochondrial function.
Specimen part, Treatment
View Samples