Dataset Information

Analysis of temporal mRNA expression changes in cultured keratinocytes from Casp-8F/–K5-Cre and Casp-8F/+K5-Cre mice

ABSTRACT: Expression of enzymatically inactive caspase-8, or deletion of caspase-8 from basal epidermal keratinocytes, triggers chronic skin inflammation in mice. Unlike similar inflammation resulting from arrest of NF-kB activation in the epidermal cells, the effect induced by caspase-8 deficiency did not depend on TNF, IL1, dermal macrophage function, or expression of the Toll-like receptor adapter proteins MyD88 or TRIF. Both interferon regulatory factor (IRF)3 and TANK-binding kinase were constitutively phosphorylated in the caspase-8-deficient epidermis, and knockdown of IRF3 in the epidermis-derived cells from these mice abolished the expression of upregulated genes. Temporal and spatial analyses of the alterations in gene expression that result from caspase-8 deficiency reveal that the changes are initiated before birth, around the time that cornification develops, and occur mainly in the suprabasal layer. Finally, we found that caspase-8-deficient keratinocytes display an enhanced response to gene activation by transfected DNA. Our findings suggest that an enhanced response to endogenous activators of IRF3 in the epidermis, presumably generated in association with keratinocyte differentiation, contributes to the skin inflammatory process triggered by caspase-8 deficiency.

ORGANISM(S): Mus musculus

PROVIDER: GSE17345 | GEO | 2009/07/29

SECONDARY ACCESSION(S): PRJNA123609

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Hair follicle formation depends on reciprocal epidermal-dermal interactions and occurs during skin development, but not in adult life. This suggests that the properties of dermal fibroblasts change during postnatal development. To examine this, we used a PdgfraEGFP mouse line to isolate GFP-positive fibroblasts from neonatal skin, adult telogen and anagen skin and adult skin in which ectopic hair follicles had been induced (EF skin) by transgenic epidermal activation of beta-catenin. We also isolated epidermal cells from each mouse. The gene expression profile of EF epidermis was most similar to that of anagen epidermis, consistent with activation of beta-catenin signalling. In contrast, adult dermis with ectopic hair follicles more closely resembled neonatal dermis than adult telogen or anagen dermis. In particular, genes associated with mitosis were upregulated and extracellular matrix-associated genes were downregulated in neonatal and EF fibroblasts. We confirmed that sustained epidermal beta-catenin activation stimulated fibroblasts to proliferate to reach the high cell density of neonatal skin. In addition, the extracellular matrix was comprehensively remodelled, with mature collagen being replaced by collagen subtypes normally present only in developing skin. The changes in proliferation and extracellular matrix composition originated from a specific subpopulation of fibroblasts located beneath the sebaceous gland. Our results show that adult dermis is an unexpectedly plastic tissue that can be reprogrammed to acquire the molecular, cellular and structural characteristics of neonatal dermis in response to cues from the overlying epidermis. We have isolated the following populations of cells from mouse back skin by flow cytometry: 1A) GFP+ WT neonatal dermal fibroblasts, 1B) ItgA6+ WT neonatal epidermal keratinocytes, 2A) GFP+ WT telogen dermal fibroblasts, 2B) ItgA6+ WT telogen epidermal keratinocytes, 3A) GFP+ D2 transient activation (anagen) dermal fibroblasts, 3B) ItgA6+ D2 transient activation (anagen) epidermal keratinocytes, 4A) GFP+ D2 sustained activation (ectopic follicles) dermal fibroblasts, 4B) ItgA6+ D2 sustained activation (ectopic follicles) epidermal keratinocytes

Dataset Information

Analysis of temporal mRNA expression changes in cultured keratinocytes from Casp-8F/–K5-Cre and Casp-8F/+K5-Cre mice

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure