Project description:Smad family proteins transduce signals downstream of transforming growth factor-beta (TGF-beta) and are one of the factors that regulate target genes related to diseases affecting the skin. We here identified C2orf54, officially known as MAB21L4, as one of the most up-regulated targets of TGF-beta and Smad3 in a differentiated human progenitor epidermal keratinocyte, using chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq). Smad2 and Smad3 bind to the regulatory regions of the C2orf54 gene locus. We found that TGF-beta induced expression of a barrier protein involucrin (encoded by IVL gene), and transcriptional activity of the IVL promoter induced by TGF-beta was inhibited by siRNAs for C2orf54. Further analysis revealed that C2orf54 siRNAs also down-regulated the expression of several target genes of TGF-beta. C2orf54 protein located mainly in the cytosol, physically bound to Smad2 and Smad3, but did not inhibit the binding of Smad2 and Smad3 to the target genomic regions. These findings suggested that TGF-beta-induced C2orf54 up-regulates gene expression induced by Smads, possibly through its physical interaction with Smad proteins.
Project description:Smad proteins transduce signals downstream of transforming growth factor-b (TGF-b), and are one of the factors that regulate the expression of genes related to diseases affecting the skin. In the present study, we identified MAB21L4, also known as male abnormal 21 like 4 or C2orf54, as one of the most up-regulated targets of TGF-b and Smad3 in differentiated human progenitor epidermal keratinocytes using chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq). Smad2 and Smad3 bound to the regulatory regions of the MAB21L4 gene locus. We found that TGF-b induced expression of the barrier protein involucrin (encoded by the IVL gene). Transcriptional activity of the IVL promoter induced by TGF-b was inhibited by siRNAs for MAB21L4. Further analysis revealed that MAB21L4 siRNAs also down-regulated the expression of several target genes of TGF-b. MAB21L4 protein was located mainly in the cytosol, where it was physically bound to Smad3 and a transcriptional corepressor c-Ski. siRNAs for MAB21L4 did not inhibit the binding of Smad3 to their target genomic regions but down-regulated acetylation of histone H3 lys 27 (H3K27ac), an active enhancer mark, near the Smad3 binding regions. These findings suggest that TGF-b-induced MAB21L4 up-regulates the gene expression induced by TGF-b, possibly through physical interactions with a transcriptional corepressor c-Ski in the cytosol.
Project description:Smad family proteins transduce signals downstream of transforming growth factor-beta (TGF-beta) and are one of the factors that regulate target genes related to diseases affecting the skin. We here identified C2orf54, officially known as MAB21L4, as one of the most up-regulated targets of TGF-beta and Smad3 in a differentiated human progenitor epidermal keratinocyte, using chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq). Smad2 and Smad3 bind to the regulatory regions of the C2orf54 gene locus. We found that TGF-beta induced expression of a barrier protein involucrin (encoded by IVL gene), and transcriptional activity of the IVL promoter induced by TGF-beta was inhibited by siRNAs for C2orf54. Further analysis revealed that C2orf54 siRNAs also down-regulated the expression of several target genes of TGF-beta. C2orf54 protein located mainly in the cytosol, physically bound to Smad2 and Smad3, but did not inhibit the binding of Smad2 and Smad3 to the target genomic regions. These findings suggested that TGF-beta-induced C2orf54 up-regulates gene expression induced by Smads, possibly through its physical interaction with Smad proteins.
Project description:Performing global gene expression profiling for different types of keratinocytes colonies can provide important information that might help in understanding the biology and ontogeny of epidermal skin stem cells. We used microarrays to detail the global gene expression profiling for different types of keratinocytes colonies including Holoclones (stem cells), Meroclones (transient amplifying cells), and Paraclones (differentiated cells) .
Project description:Human epidermal keratinocytes were treated with 25 ng.ml EphB2 or EFNA4, both as-Fc conjugates (Sigma). Human epidermal keratinocytes are treated with 25 ng/ml EphB2 or EFNA4 Fc conjugates in a 48hr time course.
Project description:The regulatory circuits that coordinate epidermal differentiation during development are still not fully understood. Here we report that the transcriptional regulator ID1 is enriched in basal epidermal progenitor cells and find ID1 expression to be diminished upon differentiation. In utero silencing of Id1 impairs progenitor cell proliferation, leads to precocious delamination of targeted progenitor cells and enables differentiated keratinocytes to retain progenitor markers and characteristics. Transcriptional profiling suggests ID1 acts by mediating adhesion to the basement membrane while inhibiting spinous layer differentiation. Co-immunoprecipitation reveals ID1 binding to transcriptional regulators of the class I bHLH family. We localize bHLH Tcf3, Tcf4 and Tcf12 to epidermal progenitor cells during epidermal stratification and established TCF3 as a downstream effector of ID1-mediated epidermal proliferation. Finally, we identify crosstalk between CEBPA, a known mediator of epidermal differentiation, and Id1 and demonstrate that CEBPA antagonizes BMP-induced activation of Id1. Our work establishes ID1 as a key coordinator of epidermal development, acting to balance progenitor proliferation with differentiation and unveils how functional crosstalk between CEBPA and Id1 orchestrates epidermal lineage progression.
Project description:Targets of Retinoic Acid (RA) were identified in primary human epidermal keratinocytes grown in the presence or absence of all-trans retinoic acid for 1, 4, 24, 48 and 72 hours. Targets of Thyroid Hormone (T3) were identified in primary human epidermal keratinocytes grown in the presence or absence of the hormone; same controls as for RA.
Project description:Targets of Retinoic Acid (RA) were identified in primary human epidermal keratinocytes grown in the presence or absence of all-trans retinoic acid for 1, 4, 24, 48 and 72 hours. Targets of Thyroid Hormone (T3) were identified in primary human epidermal keratinocytes grown in the presence or absence of the hormone; same controls as for RA. Time course, 1, 4, 24, 48 and 72 hours