Browse
Submit Data
Databases
API
Help

Dataset Information

21 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Remodeling of three-dimensional organization of the nucleus during terminal keratinocyte differentiation in the epidermis.

ABSTRACT: The nucleus of epidermal keratinocytes (KCs) is a complex and highly compartmentalized organelle, whose structure is markedly changed during terminal differentiation and transition of the genome from a transcriptionally active state seen in the basal and spinous epidermal cells to a fully inactive state in the keratinized cells of the cornified layer. Here, using multicolor confocal microscopy, followed by computational image analysis and mathematical modeling, we demonstrate that in normal mouse footpad epidermis, transition of KCs from basal epidermal layer to the granular layer is accompanied by marked differences in nuclear architecture and microenvironment including the following: (i) decrease in the nuclear volume; (ii) decrease in expression of the markers of transcriptionally active chromatin; (iii) internalization and decrease in the number of nucleoli; (iv) increase in the number of pericentromeric heterochromatic clusters; and (v) increase in the frequency of associations between the pericentromeric clusters, chromosomal territory 3, and nucleoli. These data suggest a role for nucleoli and pericentromeric heterochromatin clusters as organizers of nuclear microenvironment required for proper execution of gene expression programs in differentiating KCs, and provide important background information for further analyses of alterations in the topological genome organization seen in pathological skin conditions, including disorders of epidermal differentiation and epidermal tumors.

SUBMITTER: Gdula MR

PROVIDER: S-EPMC4135477 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Four-dimensional, dynamic mosaicism is a hallmark of normal human skin that permits mapping of the organization and patterning of human epidermis during terminal differentiation.

Project description:Recent findings of mosaicism (DNA sequence variation) challenge the dogma that each person has a stable genetic constitution. Copy number variations, point mutations and chromosome abnormalities in normal or diseased tissues have been described. We studied normal skin mosaicism of a single nucleotide polymorphism (SNP) [rs1426654, p.Thr111Ala] in SLC24A5, an ion transporter gene. This SNP is unusual in that more than 90% of people of European descent have homozygous germline A/A alleles, while more than 90% of East Asians and Blacks have homozygous germline G/G alleles. We found mosaicism in neonatal foreskins as well as in 69% of nearly 600 skin surface scraping samples from 114 donors of different ages. Strikingly, donors with germline (buccal or blood) A/A, A/G or G/G genotypes had all three sequences (A/A, A/G or G/G) in the skin surface scrapings. SNP sequence differences extended within the epidermis in the vertical dimension from basal cell layer to the stratum corneum at the surface, as well as across the two-dimensions of the skin surface. Furthermore, repeated scrapings in the same location revealed variation in the sequences in the same individuals over time, adding a fourth dimension to this variation. We then used this mosaicism to track the movement of epidermal cells during normal differentiation and characterize the patterning of epidermal cells during terminal differentiation. In this coordinated proliferation model of epidermal differentiation, the skin surface is alternatively populated by synchronous, cycling of waves of cells, with each group having a different DNA sequence. These groups of cells abruptly flatten into large sheets at the surface providing patches of uniform SNP sequence. This four-dimensional mosaicism is a normal, previously unrecognized form of dynamic mosaicism in human skin.

| S-EPMC5999106 | biostudies-literature

Expression of N-terminal truncated desmoglein 3 (deltaNDg3) in epidermis and its role in keratinocyte differentiation.

Project description:During a search for keratinocyte differentiation-related genes, we obtained a cDNA fragment from the 5'-untranslated region of a previously identified splicing variant of desmoglein 3 (Dg3). This transcript encodes a protein of 282 amino acids, which corresponds to the N-terminal truncated intracellular domain of Dg3 (deltaNDg3). Northern blot analysis detected a 4.6-kb transcript matching the predicted size of deltaNDg3 mRNA, and Western blot analysis with an antibody raised against the Dg3 C-terminus (H-145) detected a 31-kDa protein. Increased deltaNDg3 expression was observed in differentiating keratinocytes by RT-PCR and Western blot analysis, suggesting that deltaNDg3 is indeed a differentiation-related gene product. In immunohistochemical studies of normal and pathologic tissues, H-145 antibody detected the protein in the cytoplasm of suprabasal layer cells, whereas an antibody directed against the N-terminal region of Dg3 (AF1720) reacted with a membrane protein in the basal layer. In addition, deltaNDg3 transcript and protein were upregulated in psoriatic epidermis, and protein expression appeared to increase in epidermal tumors including Bowen's disease and squamous cell carcinoma. Moreover, overexpression of deltaNDg3 led to increased migration and weakening of cell adhesion. These results suggest that deltaNDg3 have a role in keratinocyte differentiation, and that may be related with tumorigenesis of epithelial origin.

| S-EPMC2679284 | biostudies-literature

Multiple pathways are involved in DNA degradation during keratinocyte terminal differentiation.

Project description:Loss of the nucleus is a critical step in keratinocyte terminal differentiation. To elucidate the mechanisms involved, we focused on two characteristic events: nuclear translocation of N-terminal fragment of profilaggrin and caspase-14-dependent degradation of the inhibitor of caspase-activated DNase (ICAD). First, we demonstrated that epidermal mesotrypsin liberated a 55-kDa N-terminal fragment of profilaggrin (FLG-N) and FLG-N was translocated into the nucleus. Interestingly, these cells became TUNEL positive. Mutation in the mesotrypsin-susceptible Arg-rich region between FLG-N and the first filaggrin domain abolished these changes. Furthermore, caspase-14 caused limited proteolysis of ICAD, followed by accumulation of caspase-activated DNase (CAD) in TUNEL-positive nuclei. Knockdown of both proteases resulted in a significant increase of remnant nuclei in a skin equivalent model. Immunohistochemical study revealed that both caspase-14 and mesotrypsin were markedly downregulated in parakeratotic areas of lesional skin from patients with atopic dermatitis and psoriasis. Collectively, our results indicate that at least two pathways are involved in the DNA degradation process during keratinocyte terminal differentiation.

| S-EPMC4001300 | biostudies-literature

Interleukin-17A suppresses granular layer formation in a three-dimensional human epidermis model via regulation of terminal differentiation genes

Project description:Immunotherapies targeting IL-17 greatly improve plaque psoriasis. Most previous studies on IL-17 focused on the Th17 immune response, but investigation of the effects of IL-17A on psoriatic epidermal structure are limited. Using an in vitro three-dimensional (3D) human epidermis model, we investigated the effects of IL-17A and IL-17C on morphological changes and gene expression. IL-17A directly suppressed the formation of the granular layer, whereas IL-17C did not. IL-17A significantly downregulated the gene expression of profilaggrin (FLG), which is a major component of keratohyalin granules in the granular layer. Global gene expression analysis of this 3D epidermis model showed that both IL-17A and IL-17C upregulated S100A7A and type 1 interferon-related genes including MX1, IFI44L, XAF1 and IFIT1. However, only IL-17A directly downregulated keratinocyte differentiation-related and cornified envelope-related genes including FLG, LOR, C1ORF68, LCE1E, LCE1B, KRT10, CST6 and RPTN. In conclusion, IL-17A, a systemic inflammatory cytokine, affected keratinization in our 3D epidermis model. In contrast, IL-17C, a locally produced cytokine, did not have strong effects on keratinization. Targeting IL-17A does not only reduce inflammation but it may also directly affect epidermal differentiation in psoriasis.

2020-12-31 | GSE142552 | GEO

Regional myocardial three-dimensional principal strains during postinfarction remodeling.

Project description:The purpose of this study was to quantify myocardial three-dimensional (3D) principal strains as the left ventricle (LV) remodels after myocardial infarction (MI). Serial quantification of myocardial strains is important for understanding the mechanical response of the LV to MI. Principal strains convert the 3D LV wall-based strain matrix with three normal and three shear elements, to a matrix with three nonzero normal elements, thereby eliminating the shear elements, which are difficult to physically interpret.The study was designed to measure principal strains of the remote, border zone, and infarct regions in a porcine model of post-MI LV remodeling. Magnetic resonance imaging was used to measure function and strain at baseline, 1 week, and 4 weeks after infarct. Principal strain was measured using 3D acquisition and the optical flow method for displacement tracking.Principal strains were altered as the LV remodeled. Maximum principal strain magnitude decreased in all regions, including the noninfarcted remote, while maximum principal strain angles rotated away from the radial direction in the border zone and infarct. Minimum principal strain magnitude followed a similar pattern; however, strain angles were altered in all regions. Evolution of principal strains correlated with adverse LV remodeling.Using a state-of-the-art imaging and optical flow method technique, 3D principal strains can be measured serially after MI in pigs. Results are consistent with progressive infarct stretching as well as with decreased contractile function in the border zone and remote myocardial regions.

| S-EPMC4352409 | biostudies-literature

Effect of air-liquid interface stimulation on gene expression during keratinocyte differentiation by three-dimensional culture

Project description:To investigate how air-liquid interface stimulation induces epidermal differentiation, we carried out RNA-seq on three-dimensional culture with and without air exposure.

2022-12-08 | GSE205727 | GEO

Three-dimensional chromatin re-organization during muscle stem cell aging

Project description:Age-related skeletal muscle atrophy or sarcopenia is a significant societal problem that is becoming amplified as the world’s population continues to increase. A critical contributor to sarcopenia is the loss in the number and function of muscle stem cells, which maintain tissue homeostasis and regenerate damage. The molecular mechanisms that govern muscle stem cell aging encompass changes across multiple regulatory layers and are integrated by the three-dimensional organization of the genome. To quantitatively understand how hierarchical chromatin architecture changes during muscle stem cell aging, we generated 3D chromatin conformation maps (Hi-C) and integrated these datasets with multi-omic (chromatin accessibility and transcriptome) profiles from bulk populations and single cells. We observed that muscle stem cells display static behavior at global scales of chromatin organization during aging and extensive rewiring of local contacts at finer scales that were associated with variations in transcription factor binding and aberrant gene expression. These data provide insights into genome topology as a regulator of molecular function in stem cell aging.

2023-02-02 | GSE214047 | GEO

Sumoylation dynamics during keratinocyte differentiation.

Project description:SUMO modification regulates the activity of numerous transcription factors that have a direct role in cell-cycle progression, apoptosis, cellular proliferation, and development, but its role in differentiation processes is less clear. Keratinocyte differentiation requires the coordinated activation of a series of transcription factors, and as several crucial keratinocyte transcription factors are known to be SUMO substrates, we investigated the role of sumoylation in keratinocyte differentiation. In a human keratinocyte cell line model (HaCaT cells), Ca2+-induced differentiation led to the transient and coordinated transcriptional activation of the genes encoding crucial sumoylation system components, including SAE1, SAE2, Ubc9, SENP1, Miz-1 (PIASx beta), SUMO2 and SUMO3. The increased gene expression resulted in higher levels of the respective proteins and changes in the pattern of sumoylated substrate proteins during the differentiation process. Similarly to the HaCaT results, stratified human foreskin keratinocytes showed an upregulation of Ubc9 in the suprabasal layers. Abrogation of sumoylation by Gam1 expression severely disrupted normal HaCaT differentiation, consistent with an important role for sumoylation in the proper progression of this biological process.

| S-EPMC3470114 | biostudies-literature

Forkhead Box C1 Regulates Human Primary Keratinocyte Terminal Differentiation.

Project description:The epidermis serves as a critical protective barrier between the internal and external environment of the human body. Its remarkable barrier function is established through the keratinocyte (KC) terminal differentiation program. The transcription factors specifically regulating terminal differentiation remain largely unknown. Using a RNA-sequencing (RNA-seq) profiling approach, we found that forkhead box c 1 (FOXC1) was significantly up-regulated in human normal primary KC during the course of differentiation. This observation was validated in human normal primary KC from several different donors and human skin biopsies. Silencing FOXC1 in human normal primary KC undergoing differentiation led to significant down-regulation of late terminal differentiation genes markers including epidermal differentiation complex genes, keratinization genes, sphingolipid/ceramide metabolic process genes and epidermal specific cell-cell adhesion genes. We further demonstrated that FOXC1 works down-stream of ZNF750 and KLF4, and upstream of GRHL3. Thus, this study defines FOXC1 as a regulator specific for KC terminal differentiation and establishes its potential position in the genetic regulatory network.

| S-EPMC5132327 | biostudies-literature

Three-dimensional chromatin re-organization during muscle stem cell aging [Hi-C]

2023-02-02 | GSE214045 | GEO