To obtain a separation of the epidermal and dermal compartments in order to examine compartment specific biological mechanisms in the skin we incubated 4 mm human skin punch biopsies in ammonium thiocyanate (NH4SCN). We wanted to test 1) the histological quality of the dermo-epidermal separation obtained by different incubation times 2) the amount and quality of extractable epidermal RNA, and 3) its impact on sample RNA expression profiles assessed by large-scale gene expression microarray analysis in both normal and inflamed skin. At 30 minutes incubation, the split between dermis and epidermis was not always histologically well-defined (i.e. occurred partly intra-epidermally) but varied between subjects. Consequently, curettage along the dermal surface of the biopsy was added to the procedure. This modified method resulted in an almost perfect separation of the epidermal and dermal compartments and satisfactory amounts of high-quality RNA were obtained. Hybridization to Affymetrix HG_U133A 2.0 GeneChips showed that ammonium thiocyanate incubation had a minute effect on gene expression resulting in only one significantly downregulated gene (cystatin E/M). We conclude that epidermis can be reproducibly and almost completely separated from the dermis of 4 mm skin biopsies by 30 min incubation in 3.8% ammonium thiocyanate combined with curettage of the dermal surface, producing high-quality RNA suitable for transcriptional analysis. Our refined method of dermo-epidermal separation will undoubtedly prove valuable in the many different settings, where the epidermal and dermal compartments need to be evaluated separately.
Extraction of high-quality epidermal RNA after ammonium thiocyanate-induced dermo-epidermal separation of 4 mm human skin biopsies.
Specimen part, Subject
View SamplesSequencing of 5' ends of RNA molecules from control and exosome-depleted HeLa-S3 cells. Overall design: CAGE library construction from RNA extracted from control and exosome-depleted cells.
Nuclear stability and transcriptional directionality separate functionally distinct RNA species.
No sample metadata fields
View SamplesClassical regeneration experiments in insects have demonstrated an important role for imaginal tissues (also called discs, the larval tissues that give rise to the adult appendages) in coupling tissue growth, maturation and patterning during development We used the rotund-Gal4 driver (Rn>) for disc-targeted silencing of the avalanche gene (avl; Rn>avl-RNAi), encoding a syntaxin that functions in the early endocytic machinery (H. Lu, D. Bilder, Nat Cell Biol 7, 1232; Dec, 2005). Rn>avl-RNAi discs reach near to normal size after 5 days of development, and then undergo unrestricted neoplastic growth. We were interested in identifying genes showing differential expression profiles in control and in neoplastic growth. We identified dilp8 as one of the most differentially expressed gene in control and Rn>avl-RNAi discs.
Secreted peptide Dilp8 coordinates Drosophila tissue growth with developmental timing.
Specimen part
View SamplesIn order to gain insight into relative stability of transcripts in plants that lacked m6A, we performed global mapping of uncapped and cleaved transcripts Overall design: 2 replicates of GMUCT in Arabidopsis thaliana ecotype Col-0 ABI3:MTA (mta) plants. genome-wide mapping of uncapped and cleaved transcripts (GMUCT)
N<sup>6</sup>-Methyladenosine Inhibits Local Ribonucleolytic Cleavage to Stabilize mRNAs in Arabidopsis.
Specimen part, Subject
View SamplesIn inflammatory diseases of the airway, a high level (estimated to be as high as 8 mM) of HOCl can be generated through a reaction catalyzed by the leukocyte granule enzyme myeloperoxidase (MPO). HOCl, a potent oxidative agent, causes extensive tissue injury through its reaction with various cellular substances, including thiols, nucleotides, and amines. In addition to its physiological source, HOCl can also be generated by chlorine gas inhalation from an accident or a potential terrorist attack. Despite the important role of HOCl-induced airway epithelial injury, the underlying molecular mechanism is largely unknown. In the present study, we found that HOCl induced dose-dependent toxicity in airway epithelial cells. By transcription profiling using GeneChip, we identified a battery of HOCl-inducible antioxidant genes, all of which have been reported previously to be regulated by nuclear factor erythroid-related factor 2 (Nrf2), a transcription factor that is critical to the lung antioxidant response. Consistent with this finding, Nrf2 was found to be activated time and dose dependently by HOCl. Although the epidermal growth factor receptor-MAPK pathway was also highly activated by HOCl, it was not involved in Nrf2 activation and Nrf2-dependent gene expression. Instead, HOCl-induced cellular oxidative stress appeared to lead directly to Nrf2 activation. To further understand the functional significance of Nrf2 activation, small interference RNA was used to knock down Nrf2 level by targeting Nrf2 or enhance nuclear accumulation of Nrf2 by targeting its endogenous inhibitor Keap1. By both methods, we conclude that Nrf2 directly protects airway epithelial cells from HOCl-induced toxicity.
Identification of Nrf2-dependent airway epithelial adaptive response to proinflammatory oxidant-hypochlorous acid challenge by transcription profiling.
No sample metadata fields
View SamplesMetal oxide engineered nanoparticles, which are widely used in diverse applications, are known to impact terrestrial plants. These nanoparticles have a potential to induce changes in plant tissue transcriptomes, and thereby the productivity. Here we looked at how the two commonly used nanoparticles, nano-titania (TiO2) and nano-ceria (CeO2) can impact the underlying mechanisms associated plant growth at genome level.
Molecular and physiological responses to titanium dioxide and cerium oxide nanoparticles in Arabidopsis.
Age, Specimen part
View SamplesSeed germination of a terrestrial plant constitute dynamic changes in various physiological processes related to growth and development. These physiological processes can be affected by various abiotic and biotic stressors. Here we looked at how the two commonly used nanoparticles, nano-titania (TiO2) and nano-ceria (CeO2) can impact the underlying mechanisms associated with germination at genome level.
Phenotypic and genomic responses to titanium dioxide and cerium oxide nanoparticles in Arabidopsis germinants.
Age, Specimen part, Treatment
View SamplesSkin and bladder epithelia form effective permeability barriers through the activation of distinct differentiation gene programs. Employing a genome-wide gene expression study, we identified transcription regulators whose expression correlates highly with that of differentiation markers both in bladder and skin, including the Grainyhead factor Get1/Grhl3, already known to be important for epidermal barrier formation. In the bladder, Get1 is most highly expressed in the differentiated umbrella cells and its mutation in mice leads to a defective bladder epithelial barrier formation due to failure of apical membrane specialization. Genes encoding components of the specialized urothelial membrane, the uroplakins, were downregulated in Get1-/- mice. At least one of these genes, Uroplakin II, is a direct target of Get1. The urothelial-specific activation of the Uroplakin II gene is due to selective binding of Get1 to the Uroplakin II promoter in urothelial cells, most likely regulated by histone modifications. These results demonstrate a key role for Get1 in urothelial differentiation and barrier formation.
The epidermal differentiation-associated Grainyhead gene Get1/Grhl3 also regulates urothelial differentiation.
Specimen part
View SamplesSkin and bladder epithelia form effective permeability barriers through the activation of distinct differentiation gene programs. Employing a genome-wide gene expression study, we identified transcription regulators whose expression correlates highly with that of differentiation markers both in bladder and skin, including the Grainyhead factor Get1/Grhl3, already known to be important for epidermal barrier formation. In the bladder, Get1 is most highly expressed in the differentiated umbrella cells and its mutation in mice leads to a defective bladder epithelial barrier formation due to failure of apical membrane specialization. Genes encoding components of the specialized urothelial membrane, the uroplakins, were downregulated in Get1-/- mice. At least one of these genes, Uroplakin II, is a direct target of Get1. The urothelial-specific activation of the Uroplakin II gene is due to selective binding of Get1 to the Uroplakin II promoter in urothelial cells, most likely regulated by histone modifications. These results demonstrate a key role for Get1 in urothelial differentiation and barrier formation.
The epidermal differentiation-associated Grainyhead gene Get1/Grhl3 also regulates urothelial differentiation.
Specimen part
View SamplesTelogen is not simply a quiescent part of the hair cycle
Identification of telogen markers underscores that telogen is far from a quiescent hair cycle phase.
Sex
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