Project description:Glut1 is highly expressed in basal cells of keratinocytes, but the functions and regulation of Glut1 has not been explored, here we specifically ablate Glut1 in epidermal keratinocytes to elucidate the role of glucose transport in the skin. We performed microarray analysis in WT and Glut1 deficient primary keratinocytes to determine the pathways might contribute to the impaired proliferation in Glut1 deficient keratinocytes,
Project description:Glut1 is highly expressed in basal cells of keratinocytes, but the regulation of Glut1 and expression of additional glucose transporters in the skin has not been explored, here we specifically ablate Glut1 in epidermal keratinocytes to elucidate the role of glucose transport in the keratinocytes. we performed microarray analysis in WT and Glut1 deficient primary keratinocytes to determine the pathways might contribute to the impaired proliferation in Glut1 deficient keratinocytes.
Project description:ADAM17 and EGFR are essential key players for epidermal integrity. Keratinocyte-specific deletion of ADAM17 in mice results in pronounced alterations in terminal differentiation of keratinocytes leading to severe epidermal barrier defects with enhanced transepidermal water loss. Thereby, mice deficient for ADAM17 in keratinocytes phenocopy mice with a keratinocyte-specific deletion of EGFR, highlighting the role of ADAM17 as a “ligand sheddase”, as it sheds membrane bound EGFR ligands from the cell surface and finally modulates EGFR signaling. In this study we aim for the first proteomic / degradomic approach to characterize the disruption of the ADAM17-EGFR signaling axis and its consequences for epidermal barrier formation. Proteomic profiling of the epidermal proteome of mice deficient for either ADAM17 or EGFR in keratinocytes at postnatal days 3 and 10 revealed highly similar protein alterations for ADAM17 and EGFR deficiency. These include massive proteome alterations of structural and regulatory components important for barrier formation, like transglutaminases, involucrin, S100 protein family members and S100 fused-type proteins, such as filaggrin, filaggrin-2 and hornerin. Cleavage site analysis using TAILS reveals, among other ADAM17 dependent cleavage sites, increased proteolytic processing of S100 fused-type proteins, including filaggrin-2. Alterations in proteolytic processing are supported by altered protein abundance of numerous proteases upon keratinocyte-specific Adam17 or Egfr deletion, among them kallikreins, cathepsins and their inhibitors. In addition, N-terminal proteomics indicated usage of alternative translation start sites. This study highlights the essential role of proteolytic processing for maintenance of a functional epidermal barrier. Furthermore it suggests that most defects in formation of the postnatal epidermal barrier upon keratinocyte-specific ADAM17 deletion are mediated via EGFR.
Project description:Repair of epithelial defect is complicated by infection and related metabolites. Pyocyanin is one such metabolite that is secreted during Pseudomonas aeruginosa infection. Keratinocyte migration is required for the closure of skin epithelial defects. The current work sought to understand pyocyanin-keratinocyte interaction and its significance in tissue repair. SILAC proteomics identified mitochondrial dysfunction as the top pathway responsive to pyocyanin exposure in human keratinocytes. Consistently, functional studies demonstrated mitochondrial stress, depletion of reducing equivalents, and ATP. Strikingly, despite all the above, pyocyanin markedly accelerated keratinocyte migration. Investigation of underlying mechanisms revealed a novel function of KRT6A in keratinocytes. KRT6A was pyocyanin inducible and accelerated closure of epithelial defect. Acceleration of closure was associated with poor quality healing including compromised expression of apical junction proteins. This work recognizes KRT6A for its role of enhancing keratinocyte migration under conditions of threat posed by pyocyanin. Qualitatively deficient junctional proteins under conditions of defensive acceleration of keratinocyte migration explains why an infected wound close with deficient skin barrier function as previously reported.
Project description:Ts keratinocyte has increased proliferation compare to WT keratinocyte upon TPA treatment. This result showed the different transcription regulation in Ts and WT keratinocyte upon TPA treatment. Total RNA extracted from WT or Ts keratinocytes, not treated or treated with TPA for 12 hours.
Project description:To understand the overall function of IL-17RD and IL-17RC in IL-17A signaling, RNAseq was performed with WT, Il17rc KO, and Il17rd KO primary mouse keratinocytes following IL-17A treatment along with untreated WT control. Keratinocyte from neonatal WT, Il17rd KO, and Il17rc KO mice were cultured and stimulated with IL-17A (100 ng/mL, PeproTech) for 8h.
Project description:Transcriptional coactivator Mediator complex facilitates transcription of various transcription factors. Previously, we have generated Med1 conditional null mice, where a critical subunit of Mediator, Med1, is removed from keratinocytes. Here we present evidence that ablation of Med1 accelerated epidermal regeneration after injury. As bulge keratinocyte stem cells are important contributors to regenerate epidermis, we first analyzed properties of stem cells in Med1 null mice. BrdU long retaining analysis revealed that deletion of Med1 still maintained quiescence of bulge keratinocyte stem cells, despite of general hyperplasia observed in Med1 deficient keratinocytes. Gene expression analysis demonstrated that a series of niche matrix proteins decreased in Med1 deficient keratinocytes. In contrast, the expression of stem cell marker Sox9 was not altered, suggesting stem cells are present but activated because of abnormal niche surrounding stem cells. In addition, Med1 deletion suppressed injury induced inflammatory reaction, which indirectly regulates epidermal regeneration. We also indicated that TGFβ1 significantly decreased in both bulge and epidermal keratinocytes upon Med1 deletion. Our study demonstrates that coactivator Med1 has a critical role to maintain bulge stem cells and epidermal regeneration presumably through regulation in TGFβ signaling. n=4 WT and KO (each sample contain RNA from one mouse)
Project description:Transcriptional coactivator Mediator complex facilitates transcription of various transcription factors. Previously, we have generated Med1 conditional null mice, where a critical subunit of Mediator, Med1, is removed from keratinocytes. Here we present evidence that ablation of Med1 accelerated epidermal regeneration after injury. As bulge keratinocyte stem cells are important contributors to regenerate epidermis, we first analyzed properties of stem cells in Med1 null mice. BrdU long retaining analysis revealed that deletion of Med1 still maintained quiescence of bulge keratinocyte stem cells, despite of general hyperplasia observed in Med1 deficient keratinocytes. Gene expression analysis demonstrated that a series of niche matrix proteins decreased in Med1 deficient keratinocytes. In contrast, the expression of stem cell marker Sox9 was not altered, suggesting stem cells are present but activated because of abnormal niche surrounding stem cells. In addition, Med1 deletion suppressed injury induced inflammatory reaction, which indirectly regulates epidermal regeneration. We also indicated that TGFβ1 significantly decreased in both bulge and epidermal keratinocytes upon Med1 deletion. Our study demonstrates that coactivator Med1 has a critical role to maintain bulge stem cells and epidermal regeneration presumably through regulation in TGFβ signaling. n=3 WT and KO (each group contains keratinocytes isolated from adult skins excised from 2 mice)