scholarly journals Phosphoprotein Phosphatase 1 Is Required for Extracellular Calcium-Induced Keratinocyte Differentiation

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Chandrama Shrestha ◽  
Yuanyuan Tang ◽  
Hong Fan ◽  
Lusha Li ◽  
Qin Zeng ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Second Messengers ◽  
Human Keratinocytes ◽  
Extracellular Calcium ◽  
Keratinocyte Differentiation ◽  
Differentiation Markers ◽  
Calcium Stimulation ◽  
E Cadherin

Extracellular calcium is a major regulator of keratinocyte differentiation in vitro and appears to play that role in vivo, but the mechanism is unclear. We have previously demonstrated that, following calcium stimulation, PIP5K1αis recruited by the E-cadherin-β-catenin complex to the plasma membrane where it provides the substrate PIP2 for both PI3K and PLC-γ1. This signaling pathway is critical for calcium-induced generation of second messengers including IP3 and intracellular calcium and keratinocyte differentiation. In this study, we explored the upstream regulatory mechanism by which calcium activates PIP5K1αand the role of this activation in calcium-induced keratinocyte differentiation. We found that treatment of human keratinocytes in culture with calcium resulted in an increase in serine dephosphorylation and PIP5K1αactivation. PP1 knockdown blocked extracellular calcium-induced increase in serine dephosphorylation and activity of PIP5K1αand induction of keratinocyte differentiation markers. Knockdown of PLC-γ1, the downstream effector of PIP5K1α, blocked upstream dephosphorylation and PIP5K1αactivation induced by calcium. Coimmunoprecipitation revealed calcium induced recruitment of PP1 to the E-cadherin-catenin-PIP5K1αcomplex in the plasma membrane. These results indicate that PP1 is recruited to the extracellular calcium-dependent E-cadherin-catenin-PIP5K1αcomplex in the plasma membrane to activate PIP5K1α, which is required for PLC-γ1 activation leading to keratinocyte differentiation.

scholarly journals Phosphatidylinositol-4-phosphate 5-kinase 1α Mediates Extracellular Calcium-induced Keratinocyte Differentiation

2009 ◽  
Vol 20 (6) ◽  
pp. 1695-1704 ◽  
Author(s):  
Zhongjian Xie ◽  
Sandra M. Chang ◽  
Sally D. Pennypacker ◽  
Er-Yuan Liao ◽  
Daniel D. Bikle
Keyword(s):  
Plasma Membrane ◽  
Second Messengers ◽  
Human Keratinocytes ◽  
Extracellular Calcium ◽  
Keratinocyte Differentiation ◽  
Activity Levels ◽  
Differentiation Markers ◽  
Resultant Increase ◽  
Phosphatidylinositol 4 ◽  
E Cadherin

Extracellular calcium (Cao) is a major regulator of keratinocyte differentiation, but the mechanism is unclear. Phosphatidylinositol-4-phosphate 5-kinase 1α (PIP5K1α) is critical in synthesizing phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2]. In this study, we sought to determine whether PIP5K1α plays a role in mediating the ability of Cao to induce keratinocyte differentiation. We found that treatment of human keratinocytes in culture with Cao resulted in increased PIP5K1α level and activity, as well as PI(4,5)P2 level, binding of phosphatidylinositol 3,4,5-triphosphate [PI(3,4,5)P3] to and activation of phospholipase C-γ1 (PLC-γ1), with the resultant increase in inositol 1,4,5-trisphosphate (IP3) and intracellular calcium (Cai). Knockdown of PIP5K1α in human keratinocytes blocked Cao-induced increases in the binding of PI(3,4,5)P3 to PLC-γ1; PLC-γ1 activity; levels of PI(4,5)P2, IP3, and Cai; and induction of keratinocyte differentiation markers. Coimmunoprecipitation and confocal studies revealed that Cao stimulated PIP5K1α recruitment to the E-cadherin–catenin complex in the plasma membrane. Knockdown of E-cadherin or β-catenin blocked Cao-induced activation of PIP5K1α. These results indicate that after Cao stimulation PIP5K1α is recruited by the E-cadherin–catenin complex to the plasma membrane where it provides the substrate PI(4,5)P2 for both PI3K and PLC-γ1. This signaling pathway is critical for Cao-induced generation of the second messengers IP3 and Cai and keratinocyte differentiation.

scholarly journals Commitment to differentiation and expression of early differentiation markers in murine keratinocytes in vitro are regulated independently of extracellular calcium concentrations.

1993 ◽  
Vol 123 (4) ◽  
pp. 909-919 ◽  
Author(s):  
V Drozdoff ◽  
W J Pledger
Keyword(s):  
Structural Changes ◽  
Solid Medium ◽  
Extracellular Calcium ◽  
Keratinocyte Differentiation ◽  
Differentiation Markers ◽  
Primary Mouse ◽  
Semi Solid ◽  
Mouse Keratinocytes

In the epidermis, one of the earliest characterized events in keratinocyte differentiation is the coordinate induction of a pair of keratins specifically expressed in suprabasal cells, keratin 1 (K1) and keratin 10 (K10). Both in vivo and in vitro, extracellular calcium is necessary for several biochemical and structural changes during keratinocyte differentiation. However, it has been unclear if calcium serves as a differentiation signal in keratinocytes. In these studies, expression of suprabasal keratin mRNA and protein is used to test whether the initial differentiation of primary mouse keratinocytes in vitro is dependent on changes in the concentration of extracellular calcium. K1 mRNA was expressed at low levels in cultures of keratinocytes growing on plastic in 0.05 mM calcium but in attached cells was not further induced by increases in the concentration of extracellular calcium. Suspension of the keratinocytes into semi-solid medium induced a rapid and substantial increase in both expression of K1 mRNA and in the percentage of cells expressing suprabasal keratin proteins. The induction was unaffected by the concentration of calcium in the semi-solid medium and could not be enhanced by exposing attached cells to higher calcium before suspension. The induction of K1 mRNA could be inhibited by exposure of the keratinocytes to either EGF or fibronectin. These results suggest that commitment of mouse keratinocytes to terminal differentiation is independent of extracellular calcium and may be regulated primarily by extracellular factors other than calcium.

Inhibition of cadherin function differentially affects markers of terminal differentiation in cultured human keratinocytes

1999 ◽  
Vol 112 (24) ◽  
pp. 4569-4579
Author(s):  
M.D. Hines ◽  
H.C. Jin ◽  
M.J. Wheelock ◽  
P.J. Jensen
Keyword(s):  
Terminal Differentiation ◽  
Human Keratinocytes ◽  
Keratinocyte Differentiation ◽  
Differentiation Markers ◽  
Protein Levels ◽  
Surface Molecules ◽  
Transglutaminase 1 ◽  
Differentiation Marker ◽  
E Cadherin

Cadherin function is required for normal keratinocyte intercellular adhesion and stratification. In the present study, we have investigated whether cadherin-cadherin interactions may also modulate keratinocyte differentiation, as evidenced by alterations in the levels of several differentiation markers. Confluent keratinocyte cultures, propagated in low Ca(2+) medium in which cadherins are not active, were pre-incubated with antibodies that block the function of E-cadherin and/or P-cadherin; Ca(2+)was then elevated to 1 mM to activate the cadherins and induce differentiation. In control cultures (incubated with no antibody or with antibodies to other cell surface molecules), Ca(2+) elevation induced an increase in type 1 transglutaminase, profilaggrin, and loricrin, as measured by western blotting and in agreement with previous results. However, the concurrent addition of antibodies against both E- and P-cadherin prevented this increase in transglutaminase 1 protein. Incubation with either antibody alone had no consistent effect. Profilaggrin and loricrin, which are later markers of keratinocyte differentiation, responded differently from transglutaminase 1 to addition of antibodies. In the presence of anti-E-cadherin antibody, both loricrin and profilaggrin levels were dramatically enhanced compared to the high Ca(2+) control cells, while addition of antibody to P-cadherin slightly attenuated the Ca(2+)-induced increase. In the presence of both antibodies, loricrin and profilaggrin protein levels were intermediate between those observed in the presence of either antibody alone. The expression of involucrin, however, was unaffected by addition of antibodies. In addition, effects of the anti-cadherin antibodies were not secondary to alterations in proliferation or programmed cell death, as determined by several independent assays of these processes. Thus, the consequences of cadherin inhibition depend upon both the particular cadherin and the differentiation marker under study. Taken together, these data suggest that E-cadherin and P-cadherin contribute to the orderly progression of terminal differentiation in the epidermis in multiple ways.

scholarly journals Three Constituents of Moringa oleifera Seeds Regulate Expression of Th17-Relevant Cytokines and Ameliorate TPA-Induced Psoriasis-Like Skin Lesions in Mice

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3256 ◽  
Author(s):  
Nuan Ma ◽  
Qin Tang ◽  
Wan-Ting Wu ◽  
Xin-An Huang ◽  
Qin Xu ◽  
...  
Keyword(s):  
Moringa Oleifera ◽  
Skin Diseases ◽  
Critical Role ◽  
Folk Medicine ◽  
Skin Lesions ◽  
Keratinocyte Differentiation ◽  
Therapeutic Application ◽  
Differentiation Markers

As a folk medicine, Moringa oleifera L. is used effectively to treat inflammatory conditions and skin diseases. However, its mechanism of action is not well understood, limiting its medical use. We isolated and identified three compounds, namely niazirin, marumoside A and sitosterol-3-O-β-d-glucoside, from the seeds of Moringa oleifera, and studied their effects on the expression of Th17-relevant cytokines (IL-12/IL-23 p40, IL-17A, IL-22 and IL-23 p19) using lipopolysaccharide-stimulated THP-1 cells. Additionally, as Th17 plays a critical role in the pathogenesis of psoriasis, we used a 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced psoriasis-like skin lesion mouse model to study their potential therapeutic application in vivo. The compounds suppressed the expression of IL-12/IL-23 p40, IL-17A, IL-22 and IL-23 p19 in vitro, and in vivo they ameliorated psoriasis-like skin lesions, decreased IL-17A mRNA expression, and increased the expression of keratinocyte differentiation markers. To our knowledge, this is the first report regarding the mechanism and therapeutic application of Moringa oleifera seeds to treat psoriasis-like lesions in vivo.

scholarly journals Differential expression of cyclophilin isoforms during keratinocyte differentiation

1994 ◽  
Vol 303 (3) ◽  
pp. 863-867 ◽  
Author(s):  
D Chatellard-Gruaz ◽  
J H Saurat ◽  
G Siegenthaler
Keyword(s):  
Human Skin ◽  
Gel Filtration ◽  
Human Keratinocytes ◽  
Immunosuppressive Drug ◽  
Keratinocyte Differentiation ◽  
Normal Human Skin ◽  
Normal Human ◽  
Radiobinding Assay

Cyclophilin A, the major intracellular binding protein for the immunosuppressive drug cyclosporin A (CsA), was studied in human keratinocytes during differentiation both in vivo and in vitro. Analysis of cyclophilin by gel-filtration radiobinding-assay with tritiated CsA showed one specific radioactive peak at 17 kDa. By this technique, the levels of cyclophilin (mean 55.23 +/- 8.43 pmol/mg protein) did not significantly differ during keratinocyte differentiation. When the protein extracts from calcium-induced differentiating keratinocytes and normal human skin were analysed by PAGE radiobinding-assay, two specific radioactive CsA-binding peaks were detected. The major peak (RF 0.13) was expressed in all samples (mean 47.32 +/- 17.53 pmol/mg protein) whereas the minor peak (RF 0.23) was dramatically decreased about 6-fold in abnormally differentiated skin (psoriasis) as well as in non-differentiated keratinocytes. At least six [3H]CsA-binding isoforms with pI values ranging from 5.58 to 7.75 were detected by isoelectrofocusing autoradio-blotting-assay in normal human skin; three of them immunoreacted with antibodies to cyclophilin. These results demonstrated the presence of several cyclophilin isoforms in human epidermal cells and an expression which correlated with the differentiation of human keratinocytes both in vivo and in vitro.

scholarly journals miR-24 triggers epidermal differentiation by controlling actin adhesion and cell migration

2012 ◽  
Vol 199 (2) ◽  
pp. 347-363 ◽  
Author(s):  
Ivano Amelio ◽  
Anna Maria Lena ◽  
Giuditta Viticchiè ◽  
Ruby Shalom-Feuerstein ◽  
Alessandro Terrinoni ◽  
...  
Keyword(s):  
Actin Cytoskeleton ◽  
Control Cell ◽  
Human Keratinocytes ◽  
Epidermal Differentiation ◽  
Keratinocyte Differentiation ◽  
Mouse Epidermis ◽  
Proliferating Cells ◽  
Cell Mobility

During keratinocyte differentiation and stratification, cells undergo extensive remodeling of their actin cytoskeleton, which is important to control cell mobility and to coordinate and stabilize adhesive structures necessary for functional epithelia. Limited knowledge exists on how the actin cytoskeleton is remodeled in epithelial stratification and whether cell shape is a key determinant to trigger terminal differentiation. In this paper, using human keratinocytes and mouse epidermis as models, we implicate miR-24 in actin adhesion dynamics and demonstrate that miR-24 directly controls actin cable formation and cell mobility. miR-24 overexpression in proliferating cells was sufficient to trigger keratinocyte differentiation both in vitro and in vivo and directly repressed cytoskeletal modulators (PAK4, Tks5, and ArhGAP19). Silencing of these targets recapitulated the effects of miR-24 overexpression. Our results uncover a new regulatory pathway involving a differentiation-promoting microribonucleic acid that regulates actin adhesion dynamics in human and mouse epidermis.

scholarly journals The Aryl Hydrocarbon Receptor senses the Henna pigment Lawsone and mediates Yin-Yang effects on skin homeostasis

2018 ◽  
Author(s):  
Laura Lozza ◽  
Pedro Moura-Alves ◽  
Teresa Domaszewska ◽  
Carolina Lage Crespo ◽  
Ioana Streata ◽  
...  
Keyword(s):  
Aryl Hydrocarbon Receptor ◽  
Skin Irritation ◽  
Human Keratinocytes ◽  
Skin Inflammation ◽  
Keratinocyte Differentiation ◽  
Aryl Hydrocarbon ◽  
Differentiation And Proliferation ◽  
Potential Use

As a first host barrier, the skin is constantly exposed to environmental insults that perturb its integrity. Tight regulation of skin homeostasis is largely controlled by the aryl hydrocarbon receptor (AhR). Here, we demonstrate that Henna and its major pigment, the naphthoquinone Lawsone activate AhR, both in vitro and in vivo. In human keratinocytes and epidermis equivalents, Lawsone exposure enhances the production of late epidermal proteins, impacts keratinocyte differentiation and proliferation, and regulates skin inflammation. To determine the potential use of Lawsone for therapeutic application, we harnessed human, murine and zebrafish models. In skin regeneration models, Lawsone interferes with physiological tissue regeneration and inhibits wound healing. Conversely, in a human acute dermatitis model, topical application of a Lawsone-containing cream ameliorates skin irritation. Altogether, our study reveals how a widely used natural plant pigment is sensed by the host receptor AhR, and how the physiopathological context determines beneficial and detrimental outcomes.

scholarly journals RNF141 interacts with KRAS to promote colorectal cancer progression

Oncogene ◽  
2021 ◽  
Author(s):  
Jiuna Zhang ◽  
Xiaoyu Jiang ◽  
Jie Yin ◽  
Shiying Dou ◽  
Xiaoli Xie ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Plasma Membrane ◽  
Tumor Growth ◽  
Cancer Progression ◽  
Critical Role ◽  
Ring Finger ◽  
Immunohistochemical Analysis ◽  
Bimolecular Fluorescence Complementation

AbstractRING finger proteins (RNFs) play a critical role in cancer initiation and progression. RNF141 is a member of RNFs family; however, its clinical significance, roles, and mechanism in colorectal cancer (CRC) remain poorly understood. Here, we examined the expression of RNF141 in 64 pairs of CRC and adjacent normal tissues by real-time PCR, Western blot, and immunohistochemical analysis. We found that there was more expression of RNF141 in CRC tissue compared with its adjacent normal tissue and high RNF141 expression associated with T stage. In vivo and in vitro functional experiments were conducted and revealed the oncogenic role of RNF141 in CRC. RNF141 knockdown suppressed proliferation, arrested the cell cycle in the G1 phase, inhibited migration, invasion and HUVEC tube formation but promoted apoptosis, whereas RNF141 overexpression exerted the opposite effects in CRC cells. The subcutaneous xenograft models showed that RNF141 knockdown reduced tumor growth, but its overexpression promoted tumor growth. Mechanistically, liquid chromatography-tandem mass spectrometry indicated RNF141 interacted with KRAS, which was confirmed by Co-immunoprecipitation, Immunofluorescence assay. Further analysis with bimolecular fluorescence complementation (BiFC) and Glutathione-S-transferase (GST) pull-down assays showed that RNF141 could directly bind to KRAS. Importantly, the upregulation of RNF141 increased GTP-bound KRAS, but its knockdown resulted in a reduction accordingly. Next, we demonstrated that RNF141 induced KRAS activation via increasing its enrichment on the plasma membrane not altering total KRAS expression, which was facilitated by the interaction with LYPLA1. Moreover, KRAS silencing partially abolished the effect of RNF141 on cell proliferation and apoptosis. In addition, our findings presented that RNF141 functioned as an oncogene by upregulating KRAS activity in a manner of promoting KRAS enrichment on the plasma membrane in CRC.

scholarly journals HDAC4 promotes nasopharyngeal carcinoma progression and serves as a therapeutic target

2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Chun Cheng ◽  
Jun Yang ◽  
Si-Wei Li ◽  
Guofu Huang ◽  
Chenxi Li ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Tumor Growth ◽  
Therapeutic Target ◽  
Histone Deacetylases ◽  
Migration And Invasion ◽  
Poor Overall Survival ◽  
Mesenchymal Transition ◽  
E Cadherin

AbstractHistone deacetylases (HDACs) are involved in tumor progression, and some have been successfully targeted for cancer therapy. The expression of histone deacetylase 4 (HDAC4), a class IIa HDAC, was upregulated in our previous microarray screen. However, the role of HDAC4 dysregulation and mechanisms underlying tumor growth and metastasis in nasopharyngeal carcinoma (NPC) remain elusive. Here, we first confirmed that the HDAC4 levels in primary and metastatic NPC tissues were significantly increased compared with those in normal nasopharyngeal epithelial tissues and found that high HDAC4 expression predicted a poor overall survival (OS) and progression-free survival (PFS). Functionally, HDAC4 accelerated cell cycle G1/S transition and induced the epithelial-to-mesenchymal transition to promote NPC cell proliferation, migration, and invasion in vitro, as well as tumor growth and lung metastasis in vivo. Intriguingly, knockdown of N-CoR abolished the effects of HDAC4 on the invasion and migration abilities of NPC cells. Mechanistically, HDAC3/4 binds to the E-cadherin promoter to repress E-cadherin transcription. We also showed that the HDAC4 inhibitor tasquinimod suppresses tumor growth in NPC. Thus, HDAC4 may be a potential diagnostic marker and therapeutic target in patients with NPC.

scholarly journals Norepinephrine Protects against Methamphetamine Toxicity through β2-Adrenergic Receptors Promoting LC3 Compartmentalization

2021 ◽  
Vol 22 (13) ◽  
pp. 7232
Author(s):  
Gloria Lazzeri ◽  
Carla L. Busceti ◽  
Francesca Biagioni ◽  
Cinzia Fabrizi ◽  
Gabriele Morucci ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Light Chain ◽  
Adrenergic Receptors ◽  
Cell Damage ◽  
Protective Effects ◽  
Autophagy Flux ◽  
Brain Areas ◽  
Indirect Consequence

Norepinephrine (NE) neurons and extracellular NE exert some protective effects against a variety of insults, including methamphetamine (Meth)-induced cell damage. The intimate mechanism of protection remains difficult to be analyzed in vivo. In fact, this may occur directly on target neurons or as the indirect consequence of NE-induced alterations in the activity of trans-synaptic loops. Therefore, to elude neuronal networks, which may contribute to these effects in vivo, the present study investigates whether NE still protects when directly applied to Meth-treated PC12 cells. Meth was selected based on its detrimental effects along various specific brain areas. The study shows that NE directly protects in vitro against Meth-induced cell damage. The present study indicates that such an effect fully depends on the activation of plasma membrane β2-adrenergic receptors (ARs). Evidence indicates that β2-ARs activation restores autophagy, which is impaired by Meth administration. This occurs via restoration of the autophagy flux and, as assessed by ultrastructural morphometry, by preventing the dissipation of microtubule-associated protein 1 light chain 3 (LC3) from autophagy vacuoles to the cytosol, which is produced instead during Meth toxicity. These findings may have an impact in a variety of degenerative conditions characterized by NE deficiency along with autophagy impairment.

Sign in / Sign up

Export Citation Format

Share Document