Wound healing is an essential homeostatic mechanism that maintains the epithelial barrier integrity after tissue damage. Although we know the main events participating in the healing of a wound, many of the underlying molecular mechanisms remain unclear. Genetically amenable systems, such as wound healing in Drosophila imaginal discs, do not model all aspects of the repair process, but allow exploring many unanswered features of the healing response; e.g., which are the signal(s) responsible for initiating tissue remodeling? How is the sealing of the epithelia achieved? Or which are the inhibitory cues that cancel the healing machinery upon completion? Answering these and other questions demands in first place the identification and functional analysis of wound-specific genes. A variety of different microarray analyses of murine and humans have identified characteristic profiles of gene expression at the wound site, however, very few functional studies in healing regulation have been carried out. We developed an experimentally controlled method to culture imaginal discs that allows live imaging and biochemical analysis and is healing-permissive. Employing this approach, we performed a comparative genome-wide profiling between those Drosophila imaginal cells actively involved in healing versus their non-engaged siblings. This lets us identify a set of potential wound-specific genes. Importantly, besides identifying and categorizing new genes, we functionally tested many of their gene products by genetic interference and overexpression in a healing assay. This non-saturated analysis defines a relevant set of new genes whose changes in expression levels are functionally significant for proper tissue repair. There is promise that our newly identified wound-healing genes will guide future work in the more complex mammalian wound response.
Identification and functional analysis of healing regulators in Drosophila.
Specimen part, Treatment
View SamplesCultures of primary human airway epithelial cells (HAE cells) were exposed to an MDCK equivalent MOI of 0.01 of several swine- and human-origin influenza viruses and RNA was extracted at the 12, 16, and 24 hours post infection.
25-Hydroxycholesterol acts as an amplifier of inflammatory signaling.
Specimen part
View SamplesDyskeratosis congenita is a bone marrow failure syndrome characterized by the presence of short telomeres at presentation. The X-linked form is caused by mutations in the gene DKC1, encoding the protein dyskerin. Dyskerin is required for in the assembly and stability of telomerase and is also involved in ribosomal RNA (rRNA) processing where it converts specific uridines to pseudouridine. DC is thought to result from failure to maintain tissues, like blood, that are renewed by stem cell activity, suggesting induced pluripotent stem (iPS) cells from X-linked DC patients may provide information about the mechanisms involved. Here we show that in iPS cells with DKC1 mutations Q31E, A353V and L37 telomere maintenance is compromised with short telomere lengths and decreased telomerase activity. The degree to which telomere lengths are affected by expression of telomerase during reprograming, or with ectopic expression of wild type dyskerin varies, with recurrent mutation A353V showing the most severe effect on telomere maintenance. A353V cells but not Q31E or L37 cells, are refractory to correction by incorporation of a single copy of a wild type DKC1 cDNA into the AAVS1 safe harbor locus. None of the mutant cells show decreased pseudouridine levels in rRNA or defective rRNA processing. Finally transcriptome analysis of the iPS cells shows that WNT signaling is significantly decreased in all mutant cells, raising the possibility that defective WNT signaling may contribute to disease pathogenesis.
Impaired Telomere Maintenance and Decreased Canonical WNT Signaling but Normal Ribosome Biogenesis in Induced Pluripotent Stem Cells from X-Linked Dyskeratosis Congenita Patients.
Specimen part
View SamplesWhen assembling a nephron during development a multipotent stem cell pool becomes restricted as differentiation ensues. A faulty differentiation arrest in this process leads to transformation and initiation of a Wilms'' tumor. Mapping these transitions with respective surface markers affords accessibility to specific cell subpopulations. NCAM1 and CD133 have been previously suggested to mark human renal progenitor populations. Herein, using cell sorting, RNA sequencing, in vitro studies with serum-free media and in vivo xenotransplantation we demonstrate a sequential map that links human kidney development and tumorigenesis; In nephrogenesis, NCAM1+CD133- marks SIX2+ multipotent renal stem cells transiting to NCAM1+CD133+ differentiating segment-specific SIX2- epithelial progenitors and NCAM1-CD133+ differentiated nephron cells. In tumorigenesis, NCAM1+CD133- marks SIX2+ blastema that includes the ALDH1+ WT cancer stem/initiating cells, while NCAM1+CD133+ and NCAM1-CD133+ specifying early and late epithelial differentiation, are severely restricted in tumor initiation capacity and tumor self-renewal. Thus, negative selection for CD133 is required for defining NCAM1+ nephron stem cells in normal and malignant nephrogenesis. Overall design: Human fetal kidney mRNA profiles of 3 cell populations (NCAM1+/CD133-, NCAM+/CD133+, NCAM-/CD133+) were generated by deep sequencing using Illumina HiSeq.
Dissecting Stages of Human Kidney Development and Tumorigenesis with Surface Markers Affords Simple Prospective Purification of Nephron Stem Cells.
No sample metadata fields
View SamplesA set of changes is identified in the transcription profile associated with the long-term, but not the acute, response to radiation exposure. The study was performed in vivo using zebrafish.
Long-term effects of ionizing radiation on gene expression in a zebrafish model.
Age, Specimen part, Treatment
View SamplesThymic-derived natural T regulatory cells (nTregs) are characterized by functional and phenotypic heterogeneity. Recently, a small fraction of peripheral Tregs have been shown to express Klrg1, but it remains unclear the extent Klrg1 defines a unique Treg subset. Here we show that Klrg1+ Tregs represent a terminally differentiated Treg subset derived from Klrg1- Tregs. This subset is a recent antigen-responsive and a highly activated short-lived Treg population that expresses enhanced levels of Treg suppressive molecules and that preferentially resides within mucosal tissues. The development of Klrg1+ Tregs also requires extensive IL-2R signaling. This activity represents a distinct function for IL-2, independent from its contribution to Treg homeostasis and competitive fitness. These and other properties are analogous to terminally differentiated short-lived CD8+ T effector cells. Our findings suggest that an important pathway driving antigen-activated conventional T lymphocytes also operates for Tregs.
IL-2 receptor signaling is essential for the development of Klrg1+ terminally differentiated T regulatory cells.
Sex, Specimen part
View SamplesTranscriptome analysis of nucleus accumbens shell samples from RAR-null mutant mice and their wild type littermates
Genome-wide Analysis of RARβ Transcriptional Targets in Mouse Striatum Links Retinoic Acid Signaling with Huntington's Disease and Other Neurodegenerative Disorders.
Sex
View SamplesTwo biological replicate experiments were performed to estimate the bias of the gene expression pattern of infected and non-infected HEp-2 cells. Microarrays hybridized with RNA from 2 h of non-infected HEp-2 cells were used as reference chips for the comparison with microarrays hybridized with RNA from 2 h and 4 h of eukaryotic cells exposed to wt-bacteria and .fasX-mutant. As a reference for chips hybridized with RNA prepared from 6 h p. i. and 8 h p. i. of both GAS-infected HEp-2 cells we used chips that were hybridized with RNA isolated from non-infected cells 8 h p. i. We also compared the microarray data from 2 h of non-infected HEp-2 cells with those from 8 h of non-infected HEp-2 cells to determine the influence of the extended culture on the non-infected cells. Only such genes which were differentially regulated after infection with wt-bacteria and .fasX-mutant infected cells and not differentially present in unequal amounts between the 2 h and 8 h of controls were included in the subsequent statistical analysis.
Global epithelial cell transcriptional responses reveal Streptococcus pyogenes Fas regulator activity association with bacterial aggressiveness.
Disease, Disease stage, Cell line, Time
View SamplesGene expression profiles were compared between regulatory T cells (Treg) and Effector CD4+ T cells in healthy B6 mice and sick mice with scurfy mutation.
Foxp3-deficient regulatory T cells do not revert into conventional effector CD4+ T cells but constitute a unique cell subset.
Sex, Specimen part
View SamplesIRE1a is a critical modulator of the unfolded protein response. Its RNAse activity generates the mature transcript for the XBP1 transcription factor and also degrades other ER associated mRNAs in a process termed Regulated IRE1a Dependent mRNA Decay or RIDD. To determine if IRE1a is critical in the response to oncogenic Ras we used ShRNA to knockdown Ire1a or Xbp1 in primary mouse epidermal keratinocytes transduced with a v-HRAS retrovirus.
ER stress and distinct outputs of the IRE1α RNase control proliferation and senescence in response to oncogenic Ras.
No sample metadata fields
View Samples