101
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Tommasi C, Rogerson C, Depledge DP, Jones M, Naeem AS, Venturini C, Frampton D, Tutill HJ, Way B, Breuer J, O'Shaughnessy RFL. Kallikrein-Mediated Cytokeratin 10 Degradation Is Required for Varicella Zoster Virus Propagation in Skin. J Invest Dermatol 2019; 140:774-784.e11. [PMID: 31626786 DOI: 10.1016/j.jid.2019.08.448] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 08/29/2019] [Accepted: 08/29/2019] [Indexed: 11/30/2022]
Abstract
Varicella zoster virus (VZV) is a skin-tropic virus that infects epidermal keratinocytes and causes chickenpox. Although common, VZV infection can be life-threatening, particularly in the immunocompromized. Therefore, understanding VZV-keratinocyte interactions is important to find new treatments beyond vaccination and antiviral drugs. In VZV-infected skin, kallikrein 6 and the ubiquitin ligase MDM2 are upregulated concomitant with keratin 10 (KRT10) downregulation. MDM2 binds to KRT10, targeting it for degradation via the ubiquitin-proteasome pathway. Preventing KRT10 degradation reduced VZV propagation in culture and prevented epidermal disruption in skin explants. KRT10 knockdown induced expression of NR4A1 and enhanced viral propagation in culture. NR4A1 knockdown prevented viral propagation in culture, reduced LC3 levels, and increased LAMP2 expression. We therefore describe a drug-able pathway whereby MDM2 ubiquitinates and degrades KRT10, increasing NR4A1 expression and allowing VZV replication and propagation.
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Affiliation(s)
- Cristina Tommasi
- Livingstone Skin Research Centre, Immunobiology and Dermatology, University College London Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Clare Rogerson
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, United Kingdom
| | - Daniel P Depledge
- Infection and Immunity, University College London, London, United Kingdom; Department of Microbiology, New York University, New York, New York
| | - Meleri Jones
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, United Kingdom; Infection and Immunity, University College London, London, United Kingdom
| | - Aishath S Naeem
- Livingstone Skin Research Centre, Immunobiology and Dermatology, University College London Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Cristina Venturini
- Infection and Immunity, University College London, London, United Kingdom
| | - Dan Frampton
- Infection and Immunity, University College London, London, United Kingdom
| | - Helena J Tutill
- Infection and Immunity, University College London, London, United Kingdom
| | - Benjamin Way
- Livingstone Skin Research Centre, Immunobiology and Dermatology, University College London Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Judith Breuer
- Infection and Immunity, University College London, London, United Kingdom
| | - Ryan F L O'Shaughnessy
- Livingstone Skin Research Centre, Immunobiology and Dermatology, University College London Great Ormond Street Institute of Child Health, London, United Kingdom; Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, United Kingdom.
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102
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Koenig U, Robenek H, Barresi C, Brandstetter M, Resch GP, Gröger M, Pap T, Hartmann C. Cell death induced autophagy contributes to terminal differentiation of skin and skin appendages. Autophagy 2019; 16:932-945. [PMID: 31379249 PMCID: PMC7144843 DOI: 10.1080/15548627.2019.1646552] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
In the adult mammalian skin, cells are constantly renewing, differentiating and moving upward, to finally die in a yet not fully understood manner. Here, we provide evidence that macroautophagy/autophagy has a dual role in the skin. In addition to its known catabolic protective role as an evolutionary conserved upstream regulator of lysosomal degradation, we show that autophagy induced cell death (CDA) occurs in epithelial lineage-derived organs, such as the inter-follicular epidermis, the sebaceous- and the Harderian gland. By utilizing GFP-LC3 transgenic and ATG7-deficient mice, we show that CDA is initiated during terminal differentiation at a stage when the cells have become highly resistant to apoptosis. In these transitional cells, the Golgi compartment expands, which accounts for the formation of primary lysosomes, and the nucleus starts to condense. During CDA a burst of autophagosome formation is observed, first the endoplasmic reticulum (ER) is phagocytosed followed by autophagy of the nucleus. By this selective form of cell death, most of the cytoplasmic organelles are degraded, but structural proteins remain intact. In the absence of autophagy, consequently, parts of the ER, ribosomes, and chromatin remain. A burst of autophagy was stochastically observed in single cells of the epidermis and collectively in larger areas of ductal cells, arguing for a coordinated induction. We conclude that autophagy is an integral part of cell death in keratinocyte lineage cells and participates in their terminal cell fate. Abbreviations: Atg7: autophagy related 7; BECN1: beclin 1; CDA: cell death-induced autophagy; Cre: Cre-recombinase; DAPI: 4′,6-diamidino-2-phenylindole; ER: endoplasmatic reticulum; GFP: green fluorescent protein; HaGl: haderian gland; IVL: involucrin; KRT14: keratin 14; LD: lipid droplet; LSM: laser scanning microscope; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; PN: perinuclear space; RB: residual body; rER: rough endoplasmatic reticulum; SB: sebum; SG-SC: stratum granulosum – stratum corneum; SGl: sebaceous gland; SQSTM1: sequestosome 1; TEM: transmission electron microscopy; TUNEL: terminal deoxynucleotidyl transferase dUTP nick end labelling.
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Affiliation(s)
- Ulrich Koenig
- Institute of Musculoskeletal Medicine, Dept. Molecular Medicine, University Hospital Münster, Westfälische Wilhelms-Universität Münster, Münster, Germany.,Previous Address: Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Horst Robenek
- Institute of Musculoskeletal Medicine, Dept. Bone and Skeletal Research, University Hospital Münster, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Caterina Barresi
- Previous Address: Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria.,Current Address: Children´s Cancer Research Institute, Vienna, Austria
| | - Marlene Brandstetter
- Electron Microscopy Facility, Vienna Biocenter Core Facilities GmbH, Vienna, Austria
| | - Guenter P Resch
- Electron Microscopy Facility, Vienna Biocenter Core Facilities GmbH, Vienna, Austria.,Current Address: Nexperion e.U.-Solutions for Electron Microscopy, Vienna, Austria
| | - Marion Gröger
- Imaging Unit, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Thomas Pap
- Institute of Musculoskeletal Medicine, Dept. Molecular Medicine, University Hospital Münster, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Christine Hartmann
- Institute of Musculoskeletal Medicine, Dept. Bone and Skeletal Research, University Hospital Münster, Westfälische Wilhelms-Universität Münster, Münster, Germany
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103
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Eckhart L, Tschachler E, Gruber F. Autophagic Control of Skin Aging. Front Cell Dev Biol 2019; 7:143. [PMID: 31417903 PMCID: PMC6682604 DOI: 10.3389/fcell.2019.00143] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/11/2019] [Indexed: 12/13/2022] Open
Abstract
The skin forms the barrier to the environment. Maintenance of this barrier during aging requires orchestrated responses to variable types of stress, the continuous renewal of the epithelial compartment, and the homeostasis of long-lived cell types. Recent experimental evidence suggests that autophagy is critically involved in skin homeostasis and skin aging is associated with and partially caused by defects of autophagy. In the outer skin epithelium, autophagy is constitutively active during cornification of keratinocytes and increases the resistance to environmental stress. Experimental suppression of autophagy in the absence of stress is tolerated by the rapidly renewing epidermal epithelium, whereas long-lived skin cells such as melanocytes, Merkel cells and secretory cells of sweat glands depend on autophagy for cellular homeostasis and normal execution of their functions during aging. Yet other important roles of autophagy have been identified in the dermis where senescence of mesenchymal cells and alterations of the extracellular matrix (ECM) are hallmarks of aging. Here, we review the evidence for cell type-specific roles of autophagy in the skin and their differential contributions to aging.
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Affiliation(s)
- Leopold Eckhart
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Erwin Tschachler
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Florian Gruber
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria.,Christian Doppler Laboratory for Biotechnology of Skin Aging, Vienna, Austria
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104
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Lehmann SM, Leube RE, Schwarz N. Keratin 6a mutations lead to impaired mitochondrial quality control. Br J Dermatol 2019; 182:636-647. [PMID: 31004504 DOI: 10.1111/bjd.18014] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2019] [Indexed: 01/05/2023]
Abstract
BACKGROUND Epidermal differentiation is a multilevel process in which keratinocytes need to lose their organelles, including their mitochondria, by autophagy. Disturbed autophagy leads to thickening of the epidermis as seen in pachyonychia congenita (PC), a rare skin disease caused by mutations in keratins 6, 16 and 17. OBJECTIVES To ask if mitophagy, the selective degradation of mitochondria by autophagy, is disturbed in PC and, if so, at which stage. METHODS Immortalized keratinocytes derived from patients with PC were used in fluorescence-based and biochemical assays to dissect the different steps of mitophagy. RESULTS PC keratinocytes accumulated old mitochondria and displayed disturbed clearance of mitochondria after mitochondrial uncoupling. However, early mitophagy steps and autophagosome formation were not affected. We observed that autolysosomes accumulate in PC and are not sufficiently recycled. CONCLUSIONS We propose an influence of keratins on autolysosomal degradation and recycling. What's already known about this topic? Terminal epidermal differentiation is a multistep process that includes the elimination of cellular components by autophagy. Autophagy-impaired keratinocytes have been shown to result in thickening of epidermal layers. Hyperkeratosis also occurs in pachyonychia congenita (PC), a rare skin disease caused by mutations in keratins 6, 16 and 17. What does this study add? Keratins contribute to mitochondrial quality control as well as maintenance of mitochondria-endoplasmic reticulum contact sites. Keratins influence autolysosomal maturation or reformation. What is the translational message? Overaged mitochondria and autolysosomes accumulate in PC. Mutations in keratin 6a lead to severely impaired mitophagy, which might contribute to PC pathogenesis.
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Affiliation(s)
- S M Lehmann
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - R E Leube
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - N Schwarz
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
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105
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Rogerson C, O'Shaughnessy RFL. Protein kinases involved in epidermal barrier formation: The AKT family and other animals. Exp Dermatol 2019; 27:892-900. [PMID: 29845670 DOI: 10.1111/exd.13696] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/24/2018] [Indexed: 12/20/2022]
Abstract
Formation of a stratified epidermis is required for the performance of the essential functions of the skin; to act as an outside-in barrier against the access of microorganisms and other external factors, to prevent loss of water and solutes via inside-out barrier functions and to withstand mechanical stresses. Epidermal barrier function is initiated during embryonic development and is then maintained throughout life and restored after injury. A variety of interrelated processes are required for the formation of a stratified epidermis, and how these processes are both temporally and spatially regulated has long been an aspect of dermatological research. In this review, we describe the roles of multiple protein kinases in the regulation of processes required for epidermal barrier formation.
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Affiliation(s)
- Clare Rogerson
- Centre for Cell Biology and Cutaneous Research, Blizard Institute, Queen Mary University of London, London, UK
| | - Ryan F L O'Shaughnessy
- Centre for Cell Biology and Cutaneous Research, Blizard Institute, Queen Mary University of London, London, UK
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106
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Genetic Study on Small Insertions and Deletions in Psoriasis Reveals a Role in Complex Human Diseases. J Invest Dermatol 2019; 139:2302-2312.e14. [PMID: 31078570 DOI: 10.1016/j.jid.2019.03.1157] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 03/19/2019] [Accepted: 03/19/2019] [Indexed: 11/20/2022]
Abstract
Genetic studies based on single-nucleotide polymorphisms have provided valuable insights into the genetic architecture of complex diseases. However, a large fraction of heritability for most of these diseases remains unexplained, and the impact of small insertions and deletions (InDels) has been neglected. We performed a comprehensive screen on the exome sequence data of 1,326 genes using the SOAP-PopIndel method for InDels in 32,043 Chinese Han individuals and identified 29 unreported InDels within 25 susceptibility genes associated with psoriasis. Specifically, we identified 12 common, 9 low-frequency, and 8 rare InDels that explained approximately 1.29% of the heritability of psoriasis. Further analyses identified KIAA0319, RELN, NCAPG, ABO, AADACL2, LMAN1, FLG, HERC5, CCDC66, LEKR1, AFF3, ABCG2, ANXA7, SYTL2,GIPR, METTL1, and FYCO1 as unreported genes for psoriasis. In addition, identified InDels were associated with the following reported genes: IFIH1, ERAP1, ERAP2, LNPEP, UBLCP1, and STAT3; unreported independent associations for exonic InDels were found within GJB2 and ZNF816A. Our study enriched the genetic basis and pathogenesis of psoriasis and highlighted the non-negligible impact of InDels on complex human diseases.
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107
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Bocheńska K, Moskot M, Malinowska M, Jakóbkiewicz-Banecka J, Szczerkowska-Dobosz A, Purzycka-Bohdan D, Pleńkowska J, Słomiński B, Gabig-Cimińska M. Lysosome Alterations in the Human Epithelial Cell Line HaCaT and Skin Specimens: Relevance to Psoriasis. Int J Mol Sci 2019; 20:E2255. [PMID: 31067781 PMCID: PMC6539968 DOI: 10.3390/ijms20092255] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 04/29/2019] [Accepted: 05/01/2019] [Indexed: 01/02/2023] Open
Abstract
Despite the constantly updated knowledge regarding the alterations occurring in the cells of patients with psoriasis, the status and the role of the lysosome, a control center of cell metabolism, remain to be elucidated. The architecture of the epidermis is largely regulated by the action of lysosomes, possibly activating signaling pathways in the cellular crosstalk of keratinocytes-epidermal cells-with infiltrating immune cells. Thus, in the present study, lysosome alterations were examined in vitro and in situ using a two-dimensional (2D) keratinocyte model of HaCaT cells with "psoriasis-like" inflammation and skin specimens, respectively. Specific fluorescence and immunohistochemical staining showed an augmented level of acidic organelles in response to keratinocyte activation (mimicking a psoriatic condition while maintaining the membrane integrity of these structures) as compared with the control, similar to that seen in skin samples taken from patients. Interestingly, patients with the most pronounced PASI (Psoriasis Area and Severity Index), BSA (Body Surface Area), and DLQI (Dermatology Life Quality Index) scores suffered a high incidence of positive lysosomal-associated membrane protein 1 (LAMP1) expression. Moreover, it was found that the gene deregulation pattern was comparable in lesioned (PP) and non-lesioned (PN) patient-derived skin tissue, which may indicate that these alterations occur prior to the onset of the characteristic phenotype of the disease. Changes in the activity of genes encoding the microphthalmia family (MiT family) of transcription factors and mammalian target of rapamycin complex 1 (MTORC1) were also observed in the in vitro psoriasis model, indicating that the biogenesis pathway of this arm is inhibited. Interestingly, in contrast to the keratinocytes of HaCaT with "psoriasis-like" inflammation, LAMP1 was up-regulated in both PP and PN skin, which can be a potential sign of an alternative mechanism of lysosome formation. Defining the molecular profile of psoriasis in the context of "the awesome lysosome" is not only interesting, but also desired; therefore, it is believed that this paper will serve to encourage other researchers to conduct further studies on this subject.
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Affiliation(s)
- Katarzyna Bocheńska
- Department of Medical Biology and Genetics, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
| | - Marta Moskot
- Department of Medical Biology and Genetics, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Laboratory of Molecular Biology, Kładki 24, 80-822 Gdańsk, Poland.
| | - Marcelina Malinowska
- Department of Medical Biology and Genetics, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
| | | | - Aneta Szczerkowska-Dobosz
- Department of Dermatology, Venereology and Allergology, Medical University of Gdańsk, Mariana Smoluchowskiego 17, 80-214 Gdańsk, Poland.
| | - Dorota Purzycka-Bohdan
- Department of Dermatology, Venereology and Allergology, Medical University of Gdańsk, Mariana Smoluchowskiego 17, 80-214 Gdańsk, Poland.
| | - Joanna Pleńkowska
- Department of Medical Biology and Genetics, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
| | - Bartosz Słomiński
- Department of Immunology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland.
| | - Magdalena Gabig-Cimińska
- Department of Medical Biology and Genetics, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Laboratory of Molecular Biology, Kładki 24, 80-822 Gdańsk, Poland.
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108
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Mahanty S, Dakappa SS, Shariff R, Patel S, Swamy MM, Majumdar A, Setty SRG. Keratinocyte differentiation promotes ER stress-dependent lysosome biogenesis. Cell Death Dis 2019; 10:269. [PMID: 30890691 PMCID: PMC6425001 DOI: 10.1038/s41419-019-1478-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 02/12/2019] [Accepted: 02/13/2019] [Indexed: 01/09/2023]
Abstract
Keratinocytes maintain epidermal integrity through cellular differentiation. This process enhances intraorganelle digestion in keratinocytes to sustain nutritional and calcium-ionic stresses observed in upper skin layers. However, the molecular mechanisms governing keratinocyte differentiation and concomitant increase in lysosomal function is poorly understood. Here, by using primary neonatal human epidermal keratinocytes, we identified the molecular link between signaling pathways and cellular differentiation/lysosome biogenesis. Incubation of keratinocytes with CaCl2 induces differentiation with increased cell size and early differentiation markers. Further, differentiated keratinocytes display enhanced lysosome biogenesis generated through ATF6-dependent ER stress signaling, but independent of mTOR-MiT/TFE pathway. In contrast, chemical inhibition of mTORC1 accelerates calcium-induced keratinocyte differentiation, suggesting that activation of autophagy promotes the differentiation process. Moreover, differentiation of keratinocytes results in lysosome dispersion and Golgi fragmentation, and the peripheral lysosomes showed colocalization with Golgi-tethering proteins, suggesting that these organelles possibly derived from Golgi. In line, inhibition of Golgi function, but not the depletion of Golgi-tethers or altered lysosomal acidity, abolishes keratinocyte differentiation and lysosome biogenesis. Thus, ER stress regulates lysosome biogenesis and keratinocyte differentiation to maintain epidermal homeostasis. Lysosomes are the key digestive organelles of differentiated keratinocytes in the epidermis. Mahanty et al. show that ER stress but not mTOR-MiT/TFE factors promotes lysosome biogenesis during keratinocyte differentiation, which is critical for epidermal homeostasis.
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Affiliation(s)
- Sarmistha Mahanty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India
| | - Shruthi Shirur Dakappa
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India
| | | | - Saloni Patel
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India
| | | | | | - Subba Rao Gangi Setty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India.
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109
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Cau L, Takahara H, Thompson PR, Serre G, Méchin MC, Simon M. Peptidylarginine Deiminase Inhibitor Cl-Amidine Attenuates Cornification and Interferes with the Regulation of Autophagy in Reconstructed Human Epidermis. J Invest Dermatol 2019; 139:1889-1897.e4. [PMID: 30878672 DOI: 10.1016/j.jid.2019.02.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 02/19/2019] [Accepted: 02/21/2019] [Indexed: 12/17/2022]
Abstract
Deimination, a post-translational modification catalyzed by a family of enzymes called peptidylarginine deiminases (PADs), is the conversion of arginine into citrulline residues in a protein. Deimination has been associated with numerous physiological and pathological processes. Our aim was to study its implication in the homeostasis of human epidermis, where three PADs are expressed, namely PAD1, 2, and 3. Three-dimensional reconstructed human epidermis (RHEs) were treated for 2 days with increased concentrations (0-800 μM) of Cl-amidine, a specific PAD inhibitor. Cl-amidine treatments inhibited deimination in a dose-dependent manner and were not cytotoxic for keratinocytes. At 800 μM , Cl-amidine was shown to reduce deimination by half, alter keratinocyte differentiation, decrease the number of corneocyte layers, significantly increase the number of transitional cells, induce clustering of mitochondria and of heterogeneous vesicles in the cytoplasm of granular keratinocytes, and upregulate the expression of autophagy proteins, including LC3-II, sestrin-2, and p62/SQSTM1. LC3 and PADs were further shown to partially co-localize in the upper epidermis. These results demonstrated that Cl-amidine treatments slow down cornification and alter autophagy in the granular layer. They suggest that PAD1 and/or PAD3 play a role in the constitutive epidermal autophagy process that appears as an important step in cornification.
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Affiliation(s)
- Laura Cau
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde, Institut National de la Santé Et de la Recherche Médicale, Université de Toulouse Midi-Pyrénées, Toulouse, France
| | - Hidenari Takahara
- Department of Applied Biological Resource Sciences, School of Agriculture, University of Ibaraki, Ibaraki, Japan
| | - Paul R Thompson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Guy Serre
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde, Institut National de la Santé Et de la Recherche Médicale, Université de Toulouse Midi-Pyrénées, Toulouse, France
| | - Marie-Claire Méchin
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde, Institut National de la Santé Et de la Recherche Médicale, Université de Toulouse Midi-Pyrénées, Toulouse, France
| | - Michel Simon
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde, Institut National de la Santé Et de la Recherche Médicale, Université de Toulouse Midi-Pyrénées, Toulouse, France.
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110
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Akgül B, Kirschberg M, Storey A, Hufbauer M. Human papillomavirus type 8 oncoproteins E6 and E7 cooperate in downregulation of the cellular checkpoint kinase-1. Int J Cancer 2019; 145:797-806. [PMID: 30786016 DOI: 10.1002/ijc.32223] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 02/05/2019] [Accepted: 02/12/2019] [Indexed: 12/22/2022]
Abstract
Human papillomavirus 8 (HPV8) is associated with the development of squamous cell carcinoma (SCC) of the skin. HPV-infected keratinocytes are able to override normal checkpoint control mechanisms and sustain cell cycle activity, allowing for synthesis of cellular proteins necessary for viral genome amplification. To study how HPV8 may disrupt cell cycle control, we analyzed the impact of HPV8 early gene expression on one of the key regulators of cell cycle and DNA damage response, checkpoint kinase-1 (CHK1). We found that expression of E1, E1̂E4, E2, E6 or E7 individually did not affect CHK1; however, keratinocytes expressing the complete early genome region (CER) of HPV8 showed a profound loss of CHK1 protein levels, that proved to be mediated by E6E7 co-expression. Neither CHK1 promoter regulation nor the ubiquitin-proteasome pathway are involved in HPV8-mediated CHK1 repression. However, CHK1 protein repression in organotypic skin cultures was paralleled by downregulation of the autophagy marker LC3B. Treatment of HPV8-CER expressing cells with the autophagy inhibitor Bafilomycin A1 rescued CHK1 expression and led to LC3B accumulation. Taken together, our data implicate that CHK1 autophagic degradation is enhanced by HPV8, which may contribute to the oncogenic potential of the virus.
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Affiliation(s)
- Baki Akgül
- Institute of Virology, University of Cologne, Faculty of Medicine, University Hospital of Cologne, Cologne, Germany
| | - Matthias Kirschberg
- Institute of Virology, University of Cologne, Faculty of Medicine, University Hospital of Cologne, Cologne, Germany
| | - Alan Storey
- Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Martin Hufbauer
- Institute of Virology, University of Cologne, Faculty of Medicine, University Hospital of Cologne, Cologne, Germany
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111
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Veeran S, Cui G, Shu B, Yi X, Zhong G. Curcumin-induced autophagy and nucleophagy in Spodoptera frugiperda Sf9 insect cells occur via PI3K/AKT/TOR pathways. J Cell Biochem 2019; 120:2119-2137. [PMID: 30242882 DOI: 10.1002/jcb.27520] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 07/30/2018] [Indexed: 01/24/2023]
Abstract
Compounds from plants or microbes are important resources for new natural pesticides against a wide variety of pests. The growing attention on the role of autophagy (type II cell death) in regulation of insect toxicology has propelled researchers to investigate autophagic cell death pathways. Our previous study proved that the cytotoxic effect of curcumin in Spodoptera frugiperda cells is regulated by autophagy. However, the signaling pathways and molecular mechanisms had not been determined. The current study elucidates curcumin inhibition of survival signaling by blocking the activation of PI3K/AKT/TOR pathways to induce autophagy in S. frugiperda cells. The result demonstrates that nucleophagy associated with cell death following the curcumin treatment. Following the curcumin treatment, Atg8/LC3 immunostaining in both nucleus and cytoplasm was markedly increased. Further, messenger RNA expression level of Atg8 and Atg1 genes regulation by curcumin was examined using quantitative reverse transcription polymerase chain reaction, and the result exhibited increased level of expression after curcumin treatment in a time-dependent manner. Our current study provides new insights to the autophagy occurring via PI3K/AKT/TOR pathways in S. frugiperda Sf9 insect cells induced by curcumin. Taken together, our results show for the first time that curcumin induced nucleophagy in lepidopteron insect cell line.
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Affiliation(s)
- Sethuraman Veeran
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou, China.,Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China
| | - Gaofeng Cui
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou, China.,Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China
| | - Benshui Shu
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou, China.,Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China
| | - Xin Yi
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou, China.,Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China
| | - Guohua Zhong
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou, China.,Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China
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112
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Li L, Zhang J, Zhang Q, Zhang D, Xiang F, Jia J, Wei P, Zhang J, Hu J, Huang Y. High Glucose Suppresses Keratinocyte Migration Through the Inhibition of p38 MAPK/Autophagy Pathway. Front Physiol 2019; 10:24. [PMID: 30745880 PMCID: PMC6360165 DOI: 10.3389/fphys.2019.00024] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 01/10/2019] [Indexed: 12/13/2022] Open
Abstract
Wound healing is delayed frequently in patients with diabetes. Proper keratinocyte migration is an essential step during re-epithelialization. Impaired keratinocyte migration is a critical underlying factor responsible for the deficiency of diabetic wound healing, which is mainly attributed to the hyperglycemic state. However, the underlying mechanisms remain largely unknown. Previously, we demonstrated a marked activation of p38/mitogen-activated protein kinase (MAPK) pathway in the regenerated migrating epidermis, which in turn promoted keratinocyte migration. In the present study, we find that p38/MAPK pathway is downregulated and accompanied by inactivation of autophagy under high glucose (HG) environment. In addition, we demonstrate that inactivation of p38/MAPK and autophagy result in the inhibition of keratinocyte migration under HG environment, and the activating p38/MAPK by MKK6(Glu) overexpression rescues cell migration through an autophagy-dependent way. Moreover, diabetic wound epidermis shows a significant inhibition of p38/MAPK and autophagy. Targeting these dysfunctions may provide novel therapeutic approaches.
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Affiliation(s)
- Lingfei Li
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Junhui Zhang
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Qiong Zhang
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Dongxia Zhang
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Fei Xiang
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Jiezhi Jia
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Ping Wei
- Endocrinology Department, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Jiaping Zhang
- Department of Plastic Surgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Jiongyu Hu
- State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Endocrinology Department, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Yuesheng Huang
- Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
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113
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Autophagy Activation by Crepidiastrum Denticulatum Extract Attenuates Environmental Pollutant-Induced Damage in Dermal Fibroblasts. Int J Mol Sci 2019; 20:ijms20030517. [PMID: 30691106 PMCID: PMC6386979 DOI: 10.3390/ijms20030517] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 01/22/2019] [Accepted: 01/22/2019] [Indexed: 12/12/2022] Open
Abstract
Pollution-induced skin damage results in oxidative stress; cellular toxicity; inflammation; and, ultimately, premature skin aging. Previous studies suggest that the activation of autophagy can protect oxidation-induced cellular damage and aging-like changes in skin. In order to develop new anti-pollution ingredients, this study screened various kinds of natural extracts to measure their autophagy activation efficacy in cultured dermal fibroblast. The stimulation of autophagy flux by the selected extracts was further confirmed both by the expression of proteins associated with the autophagy signals and by electron microscope. Crepidiastrum denticulatum (CD) extract treated cells showed the highest autophagic vacuole formation in the non-cytotoxic range. The phosphorylation of adenosine monophosphate kinase (AMPK), but not the inhibition of mammalian target of rapamycin (mTOR), was observed by CD-extract treatment. Its anti-pollution effects were further evaluated with model compounds, benzo[a]pyrene (BaP) and cadmium chloride (CdCl2), and a CD extract treatment resulted in both the protection of cytotoxicity and a reduction of proinflammatory cytokines. These results suggest that the autophagy activators can be a new protection regimen for anti-pollution. Therefore, CD extract can be used for anti-inflammatory and anti-pollution cosmetic ingredients.
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114
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Nucleophagy: from homeostasis to disease. Cell Death Differ 2019; 26:630-639. [PMID: 30647432 PMCID: PMC6460388 DOI: 10.1038/s41418-018-0266-5] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 12/09/2018] [Accepted: 12/17/2018] [Indexed: 11/08/2022] Open
Abstract
Nuclear abnormalities are prominent in degenerative disease and progeria syndromes. Selective autophagy of organelles is instrumental in maintaining cell homeostasis and prevention of premature ageing. Although the nucleus is the control centre of the cell by safeguarding our genetic material and controlling gene expression, little is known in relation to nuclear autophagy. Here we present recent discoveries in nuclear recycling, namely nucleophagy in physiology in yeast and nucleophagic events that occur in pathological conditions in mammals. The selective nature of degrading nuclear envelope components, DNA, RNA and nucleoli is highlighted. Potential effects of perturbed nucleophagy in senescence and longevity are examined. Moreover, the open questions that remain to be explored are discussed concerning the conditions, receptors and substrates in homeostatic nucleophagy.
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115
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Buerger C. Epidermal mTORC1 Signaling Contributes to the Pathogenesis of Psoriasis and Could Serve as a Therapeutic Target. Front Immunol 2018; 9:2786. [PMID: 30555471 PMCID: PMC6284005 DOI: 10.3389/fimmu.2018.02786] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 11/12/2018] [Indexed: 01/26/2023] Open
Abstract
Although modern biologics targeting different inflammatory mediators show promising therapeutic success, comprehensive knowledge about the molecular events in psoriatic keratinocytes that contribute to the pathogenesis and could serve as therapeutic targets is still scarce. However, recent efforts to understand the deregulated signal transduction pathways have led to the development of small molecule inhibitors e.g., tofacitinib targeting the Jak/Stat cascade that opens additional therapeutic options. Recently, the PI3-K/Akt/mTOR signaling pathway has emerged as an important player in the control of epidermal homeostasis. This review summarizes the current knowledge on the role of this pathway in the pathogenesis of psoriasis, especially the epidermal manifestation of the disease and discusses current approaches to target the pathway therapeutically.
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Affiliation(s)
- Claudia Buerger
- Department of Dermatology, Venerology and Allergology, Clinic of the Goethe University, Frankfurt am Main, Germany
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116
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Raam L, Kaleviste E, Šunina M, Vaher H, Saare M, Prans E, Pihlap M, Abram K, Karelson M, Peterson P, Rebane A, Kisand K, Kingo K. Lymphoid Stress Surveillance Response Contributes to Vitiligo Pathogenesis. Front Immunol 2018; 9:2707. [PMID: 30515176 PMCID: PMC6255962 DOI: 10.3389/fimmu.2018.02707] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 11/01/2018] [Indexed: 11/13/2022] Open
Abstract
Vitiligo is a chronic multifactorial depigmentation disorder characterized by the destruction and functional loss of melanocytes. Although a direct cytotoxic T cell attack is thought to be responsible for melanocyte damage, the events leading to the loss of self-tolerance toward melanocytic antigens are not understood. This research aimed to identify novel cellular and molecular factors that participate in vitiligo pathogenesis through the application of gene expression and immunofluorescence analysis of skin biopsy samples along with immunophenotyping of circulating cells. Our study provides insights into the mechanisms involved in melanocyte destruction. The upregulation of stress-ligand MICA/MICB, recognized by activating receptors on innate and innate-like T cells, imply involvement of lymphoid stress surveillance responses in vitiligo lesions. A simultaneous increase in the expression of transcription factor EOMES that is characteristic for innate-like virtual memory T cells, suggest a similar scenario. Local lymphoid stress surveillance has been previously associated with the amplification of systemic humoral responses that were mirrored in our study by increased T follicular helper cells and switched memory B cell proportions in patients with active vitiligo. In addition, microtubule-associated protein light chain 3 staining was compatible with the activation of autophagy in keratinocytes and in the remaining melanocytes of vitiligo lesional skin.
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Affiliation(s)
- Liisi Raam
- Department of Dermatology, University of Tartu, Tartu, Estonia.,Dermatology Clinic, Tartu University Hospital, Tartu, Estonia
| | - Epp Kaleviste
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Marina Šunina
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Helen Vaher
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Mario Saare
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Ele Prans
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Maire Pihlap
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Kristi Abram
- Department of Dermatology, University of Tartu, Tartu, Estonia.,Dermatology Clinic, Tartu University Hospital, Tartu, Estonia
| | - Maire Karelson
- Department of Dermatology, University of Tartu, Tartu, Estonia.,Dermatology Clinic, Tartu University Hospital, Tartu, Estonia
| | - Pärt Peterson
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Ana Rebane
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Kai Kisand
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Külli Kingo
- Department of Dermatology, University of Tartu, Tartu, Estonia.,Dermatology Clinic, Tartu University Hospital, Tartu, Estonia
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117
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Limi S, Senecal A, Coleman R, Lopez-Jones M, Guo P, Polumbo C, Singer RH, Skoultchi AI, Cvekl A. Transcriptional burst fraction and size dynamics during lens fiber cell differentiation and detailed insights into the denucleation process. J Biol Chem 2018; 293:13176-13190. [PMID: 29959226 DOI: 10.1074/jbc.ra118.001927] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 06/11/2018] [Indexed: 01/05/2023] Open
Abstract
Genes are transcribed in irregular pulses of activity termed transcriptional bursts. Cellular differentiation requires coordinated gene expression; however, it is unknown whether the burst fraction (i.e. the number of active phases of transcription) or size/intensity (the number of RNA molecules produced within a burst) changes during cell differentiation. In the ocular lens, the positions of lens fiber cells correlate precisely with their differentiation status, and the most advanced cells degrade their nuclei. Here, we examined the transcriptional parameters of the β-actin and lens differentiation-specific α-, β-, and γ-crystallin genes by RNA fluorescent in situ hybridization (FISH) in the lenses of embryonic day (E) E12.5, E14.5, and E16.5 mouse embryos and newborns. We found that cellular differentiation dramatically alters the burst fraction in synchronized waves across the lens fiber cell compartment with less dramatic changes in burst intensity. Surprisingly, we observed nascent transcription of multiple genes in nuclei just before nuclear destruction. Nuclear condensation was accompanied by transfer of nuclear proteins, including histone and nonhistone proteins, to the cytoplasm. Although lens-specific deletion of the chromatin remodeler SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily A member 5 (Smarca5/Snf2h) interfered with denucleation, persisting nuclei remained transcriptionally competent and exhibited changes in both burst intensity and fraction depending on the gene examined. Our results uncover the mechanisms of nascent transcriptional control during differentiation and chromatin remodeling, confirm the burst fraction as the major factor adjusting gene expression levels, and reveal transcriptional competence of fiber cell nuclei even as they approach disintegration.
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Affiliation(s)
| | | | | | | | | | | | - Robert H Singer
- Anatomy and Structural Biology.,Cell Biology.,Neuroscience, and
| | | | - Ales Cvekl
- From the Departments of Genetics, .,Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, New York 10461
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118
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Simpson CL. What's Eating the Epidermis? In Vivo Autophagy Manipulation via Subcutaneous MicroRNA Delivery. J Invest Dermatol 2018; 138:1463-1465. [PMID: 29941095 DOI: 10.1016/j.jid.2018.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 04/09/2018] [Accepted: 04/10/2018] [Indexed: 10/28/2022]
Abstract
Autophagy, discovered as a starvation-induced cellular recycling pathway, routes protein aggregates, damaged organelles, and pathogens to lysosomes and also supports normal tissue homeostasis. Although prior studies linked autophagy to epidermal differentiation, infection, and carcinogenesis, Wang et al. report upstream regulation of autophagy by microRNAs. Subcutaneous delivery of microRNA mimics and antagonists modulated autophagy in vivo, suggesting a novel potential therapeutic strategy in dermatology.
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Affiliation(s)
- Cory L Simpson
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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119
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Sil P, Wong SW, Martinez J. More Than Skin Deep: Autophagy Is Vital for Skin Barrier Function. Front Immunol 2018; 9:1376. [PMID: 29988591 PMCID: PMC6026682 DOI: 10.3389/fimmu.2018.01376] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 06/04/2018] [Indexed: 12/30/2022] Open
Abstract
The skin is a highly organized first line of defense that stretches up to 1.8 m2 and is home to more than a million commensal bacteria. The microenvironment of skin is driven by factors such as pH, temperature, moisture, sebum level, oxidative stress, diet, resident immune cells, and infectious exposure. The skin has a high turnover of cells as it continually bares itself to environmental stresses. Notwithstanding these limitations, it has devised strategies to adapt as a nutrient-scarce site. To perform its protective function efficiently, it relies on mechanisms to continuously remove dead cells without alarming the immune system, actively purging the dying/senescent cells by immunotolerant efferocytosis. Both canonical (starvation-induced, reactive oxygen species, stress, and environmental insults) and non-canonical (selective) autophagy in the skin have evolved to perform astute due-diligence and housekeeping in a quiescent fashion for survival, cellular functioning, homeostasis, and immune tolerance. The autophagic “homeostatic rheostat” works tirelessly to uphold the delicate balance in immunoregulation and tolerance. If this equilibrium is upset, the immune system can wreak havoc and initiate pathogenesis. Out of all the organs, the skin remains under-studied in the context of autophagy. Here, we touch upon some of the salient features of autophagy active in the skin.
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Affiliation(s)
- Payel Sil
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, Durham, NC, United States
| | - Sing-Wai Wong
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, Durham, NC, United States.,Oral and Craniofacial Biomedicine Curriculum, School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Jennifer Martinez
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, Durham, NC, United States
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120
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Role of Fibroblast Growth Factor Receptor 2b in the Cross Talk between Autophagy and Differentiation: Involvement of Jun N-Terminal Protein Kinase Signaling. Mol Cell Biol 2018; 38:MCB.00119-18. [PMID: 29685904 PMCID: PMC6002692 DOI: 10.1128/mcb.00119-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 04/12/2018] [Indexed: 12/21/2022] Open
Abstract
Fibroblast growth factor receptor 2b (FGFR2b) is a receptor tyrosine kinase expressed exclusively in epithelial cells. We previously demonstrated that FGFR2b induces autophagy and that this process is required for the triggering of FGFR2b-mediated early differentiation of keratinocytes. However, the molecular mechanisms regulating this interplay remain to be elucidated. Since we have also recently shown that Jun N-terminal protein kinase 1 (JNK1) signaling is involved in FGFR2b-induced autophagy and a possible role of the JNK pathway in epidermal differentiation has been suggested (though it is still debated), we investigated here the cross talk between FGFR2b-mediated autophagy and differentiation, focusing on the downstream JNK signaling. Biochemical, molecular, and immunofluorescence approaches in 2-dimensional (2-D) keratinocyte cultures and three-dimensional (3-D) organotypic skin equivalents confirmed that FGFR2b overexpression increased both autophagy and early differentiation. The use of FGFR2b substrate inhibitors and the silencing of JNK1 highlighted that this signaling is required not only for autophagy but also for the triggering of early differentiation. In contrast, the extracellular signal-regulated kinase 1 and 2 (ERK1/2) pathway did not appear to be involved in the two processes, and AKT signaling, whose activation contributes to the FGFR2b-mediated onset of keratinocyte differentiation, was not required for the triggering of autophagy. Overall, our results point to JNK1 as a signaling hub that regulates the interplay between FGFR2b-induced autophagy and differentiation.
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121
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Gauster M, Maninger S, Siwetz M, Deutsch A, El-Heliebi A, Kolb-Lenz D, Hiden U, Desoye G, Herse F, Prokesch A. Downregulation of p53 drives autophagy during human trophoblast differentiation. Cell Mol Life Sci 2018; 75:1839-1855. [PMID: 29080089 PMCID: PMC5910494 DOI: 10.1007/s00018-017-2695-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 10/20/2017] [Accepted: 10/24/2017] [Indexed: 01/21/2023]
Abstract
The placental barrier is crucial for the supply of nutrients and oxygen to the developing fetus and is maintained by differentiation and fusion of mononucleated cytotrophoblasts into the syncytiotrophoblast, a process only partially understood. Here transcriptome and pathway analyses during differentiation and fusion of cultured trophoblasts yielded p53 signaling as negative upstream regulator and indicated an upregulation of autophagy-related genes. We further showed p53 mRNA and protein levels decreased during trophoblast differentiation. Reciprocally, autophagic flux increased and cytoplasmic LC3B-GFP puncta became more abundant, indicating enhanced autophagic activity. In line, in human first trimester placenta p53 protein mainly localized to the cytotrophoblast, while autophagy marker LC3B as well as late autophagic compartments were predominantly detectable in the syncytiotrophoblast. Importantly, ectopic overexpression of p53 reduced levels of LC3B-II, supporting a negative regulatory role on autophagy in differentiating trophoblasts. This was also shown in primary trophoblasts and human first trimester placental explants, where pharmacological stabilization of p53 decreased LC3B-II levels. In summary our data suggest that differentiation-dependent downregulation of p53 is a prerequisite for activating autophagy in the syncytiotrophoblast.
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Affiliation(s)
- Martin Gauster
- Institute of Cell Biology, Histology and Embryology, Medical University Graz, Neue Stiftingtalstraße 6, F/03/38, 8010, Graz, Austria.
| | - Sabine Maninger
- Institute of Cell Biology, Histology and Embryology, Medical University Graz, Neue Stiftingtalstraße 6, F/03/38, 8010, Graz, Austria
| | - Monika Siwetz
- Institute of Cell Biology, Histology and Embryology, Medical University Graz, Neue Stiftingtalstraße 6, F/03/38, 8010, Graz, Austria
| | - Alexander Deutsch
- Division of Hematology, Department of Internal Medicine, Medical University Graz, Graz, Austria
| | - Amin El-Heliebi
- Institute of Cell Biology, Histology and Embryology, Medical University Graz, Neue Stiftingtalstraße 6, F/03/38, 8010, Graz, Austria
| | - Dagmar Kolb-Lenz
- Institute of Cell Biology, Histology and Embryology, Medical University Graz, Neue Stiftingtalstraße 6, F/03/38, 8010, Graz, Austria
- Center for Medical Research, Core Facility Ultrastructure Analysis, Medical University Graz, Graz, Austria
| | - Ursula Hiden
- Department of Obstetrics and Gynecology, Medical University Graz, Graz, Austria
| | - Gernot Desoye
- Department of Obstetrics and Gynecology, Medical University Graz, Graz, Austria
| | - Florian Herse
- Experimental and Clinical Research Center, A Joint Cooperation Between the Charité Medical Faculty and the Max-Delbrueck Center for Molecular Medicine, Berlin, Germany
- Berlin Institute of Health (BIH), Berlin, Germany
| | - Andreas Prokesch
- Institute of Cell Biology, Histology and Embryology, Medical University Graz, Neue Stiftingtalstraße 6, F/03/38, 8010, Graz, Austria.
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122
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Jones L, Harland D, Jarrold B, Connolly J, Davis M. The walking dead: sequential nuclear and organelle destruction during hair development. Br J Dermatol 2018; 178:1341-1352. [DOI: 10.1111/bjd.16148] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2017] [Indexed: 12/12/2022]
Affiliation(s)
- L.A. Jones
- Institute of Molecular and Cell Biology; Agency for Science; Technology and Research; Singapore City Singapore
| | - D.P. Harland
- Food and Bio-Based Products Group; AgResearch Ltd; Christchurch New Zealand
| | | | - J.E. Connolly
- Institute of Molecular and Cell Biology; Agency for Science; Technology and Research; Singapore City Singapore
- Institute of Biomedical Studies; Baylor University; Waco TX U.S.A
- Department of Microbiology and Immunology; National University of Singapore; Singapore City Singapore
| | - M.G. Davis
- The Procter and Gamble Company; Mason OH U.S.A
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123
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Lim J, Lim CJ, Kim S, Nam G, Chang M, Park K, Park K, Kim HJ, Ahn JK, Jeong S. Antiaging and antioxidant effects of topical autophagy activator: A randomized, placebo‐controlled, double‐blinded study. J Cosmet Dermatol 2018. [DOI: 10.1111/jocd.12530] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Jongmi Lim
- CRID Center NeoPharm Co., Ltd. Daejeon South Korea
| | - Chae Jin Lim
- Incospharm Corp. Daejeon South Korea
- Department of Microbiology and Molecular Biology School of Bioscience and Biotechnology Chungnam National University Daejeon South Korea
| | - Sungwoo Kim
- CRID Center NeoPharm Co., Ltd. Daejeon South Korea
| | - Gaewon Nam
- Department of Bio‐Cosmetic Science Seowon University Cheongju South Korea
| | - Minyoul Chang
- Department of Bio‐Cosmetic Science Seowon University Cheongju South Korea
| | | | - Kyungho Park
- Convergence Program of Material Science for Medicine and Pharmaceutics, and Department of Food Science and Nutrition Hallym University Chuncheon South Korea
| | - Hyun Jung Kim
- Department of Dermatology Seoul Medical Center Seoul Korea
| | - Jeong Keun Ahn
- Department of Microbiology and Molecular Biology School of Bioscience and Biotechnology Chungnam National University Daejeon South Korea
| | - Sekyoo Jeong
- Department of Bio‐Cosmetic Science Seowon University Cheongju South Korea
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124
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Lysosomes Support the Degradation, Signaling, and Mitochondrial Metabolism Necessary for Human Epidermal Differentiation. J Invest Dermatol 2018. [PMID: 29526763 DOI: 10.1016/j.jid.2018.02.035] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Keratinocytes undergo significant structural remodeling during epidermal differentiation, including a broad transformation of the proteome coupled with a reduction in total cellular biomass. This suggests that intracellular digestion of proteins and organelles is necessary for keratinocyte differentiation. Here, we use both genetic and pharmacologic approaches to demonstrate that autophagy and lysosomal functions are required for keratinocyte differentiation in organotypic human skin. Lysosomal activity was required for mechanistic target of rapamycin signaling and mitochondrial oxidative metabolism. In turn, mitochondrial reactive oxygen species, produced as a natural byproduct of oxidative phosphorylation, were necessary for keratinocyte differentiation. Finally, treatment with exogenous reactive oxygen species rescued the differentiation defect in lysosome-inhibited keratinocytes. These findings highlight a reciprocal relationship between lysosomes and mitochondria, in which lysosomes support mitochondrial metabolism and the associated production of mitochondrial reactive oxygen species. The mitochondrial reactive oxygen species released to the cytoplasm in suprabasal keratinocytes triggers autophagy and lysosome-mediated degradation necessary for epidermal differentiation. As defective lysosome-dependent autophagy is associated with common skin diseases including psoriasis and atopic dermatitis, a better understanding of the role of lysosomes in epidermal homeostasis may guide future therapeutic strategies.
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125
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Wang S, Kobeissi A, Dong Y, Kaplan N, Yang W, He C, Zeng K, Peng H. MicroRNAs-103/107 Regulate Autophagy in the Epidermis. J Invest Dermatol 2018; 138:1481-1490. [PMID: 29452119 DOI: 10.1016/j.jid.2018.02.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 02/03/2018] [Accepted: 02/05/2018] [Indexed: 12/23/2022]
Abstract
We have shown that microRNAs-103 and -107 (miRs-103/107) positively regulate end-stage autophagy by ensuring dynamin activity in cultured keratinocytes. Most work in end-stage autophagy has been conducted using in vitro model systems. In vivo regulation of end-stage autophagy in epidermis remains unknown. Here, we used antagomirs to subcutaneously knock down miR-107 in the skin; conversely, we delivered miR-107 mimic subcutaneously via in vivo transfection to increase this miR. We found that antagomir-107 treatment in epidermis: (i) depleted endogenous miR-107; (ii) increased GFP-LC3 puncta in epidermal basal layers of GFP-LC3 transgenic mice, indicative of an accumulation of autophagosomes; (iii) inhibited LC3 turnover and increased p62, suggesting an inhibition of autophagy flux; and (iv) increased phosphorylated dynamin (p-dynamin, an inactive form), a key enzyme in end-stage autophagy. Conversely, miR-107 mimic treatment in mouse epidermis: decreased GFP-LC3 puncta in basal layer, as well as p62 protein levels; and diminished p-dynamin, indicative of activation of this enzyme. In human epidermal keratinocytes, antagos-103/107 cause the formation of large vacuoles and an increase in p-dynamin, which can be rescued by inhibition of protein kinase C pathway. Collectively, these results suggest that the miR-103/107 family has a critical role in regulating end-stage autophagy in mouse epidermis via PLD1/2-protein kinase C-dynamin pathway.
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Affiliation(s)
- Sijia Wang
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China; Department of Dermatology, Northwestern University, Chicago, Illinois, USA
| | - Aya Kobeissi
- Department of Dermatology, Northwestern University, Chicago, Illinois, USA
| | - Ying Dong
- Department of Dermatology, Northwestern University, Chicago, Illinois, USA; Department of Ophthalmology, the First Affiliated Hospital, Chinese PLA General Hospital, Beijing, China
| | - Nihal Kaplan
- Department of Dermatology, Northwestern University, Chicago, Illinois, USA
| | - Wending Yang
- Department of Dermatology, Northwestern University, Chicago, Illinois, USA
| | - Congcong He
- Cell and Molecular Biology, Northwestern University, Chicago, Illinois, USA
| | - Kang Zeng
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
| | - Han Peng
- Department of Dermatology, Northwestern University, Chicago, Illinois, USA.
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126
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Varshney P, Saini N. PI3K/AKT/mTOR activation and autophagy inhibition plays a key role in increased cholesterol during IL-17A mediated inflammatory response in psoriasis. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1795-1803. [PMID: 29432814 DOI: 10.1016/j.bbadis.2018.02.003] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 01/25/2018] [Accepted: 02/08/2018] [Indexed: 11/29/2022]
Abstract
Psoriasis is an immune-mediated inflammatory disease of the skin. Previous studies including ours have shown that IL-17A plays a major role in its pathogenesis; however, its precise molecular mechanism of action is not well understood. Cytokines like TNF α and IL-23 are also important in mediating the disease and some studies have also reported autophagy as a novel mechanism by which cytokines controls the immune response. Herein, we investigated the effect of IL-17A on autophagy and reveal crosstalk between autophagy and cholesterol signaling in keratinocytes. Our results suggest that IL-17A stimulated keratinocytes activated PI3K/AKT/mTOR signaling and inhibited autophagy by simultaneously inhibiting autophagosome formation and enhancing autophagic flux. Western blotting was utilized to detect the expression of autophagic markers (LC3 and p62), PI3K, mTOR and AKT. Induction of autophagy by mTOR inhibitor rapamycin and/or starvation also inhibited the levels of IL-17A secreted IL-8, CCL20 and S100A7 in keratinocytes. Herein, we also observed that inhibition of autophagy by IL-17A was accompanied by enhanced cellular cholesterol levels which in turn regulated the autophagic flux. To investigate crosstalk between autophagy and cellular cholesterol, we used methyl-β-cyclodextrin (MβCD), which disrupts detergent-insoluble microdomains (DIMs) by depleting cells of cholesterol and checked autophagy. Decreased expression of LC3-II in psoriatic lesional skin compared to non-lesional skin and induction of autophagy by anti-psoriatic drug methotrexate in keratinocytes further confirms the role of autophagy in psoriasis. Our findings suggest that modulators of autophagy and/or cholesterol levels may be developed, and also may lead to new therapeutic agents for psoriasis treatment.
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Affiliation(s)
- Pallavi Varshney
- Functional Genomics Unit, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India; Academy of Scientific & Innovative Research, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007, India
| | - Neeru Saini
- Functional Genomics Unit, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India; Academy of Scientific & Innovative Research, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007, India.
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127
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Cieślar-Pobuda A, Rafat M, Knoflach V, Skonieczna M, Hudecki A, Małecki A, Urasińska E, Ghavami S, Łos MJ. Human induced pluripotent stem cell differentiation and direct transdifferentiation into corneal epithelial-like cells. Oncotarget 2018; 7:42314-42329. [PMID: 27275539 PMCID: PMC5173137 DOI: 10.18632/oncotarget.9791] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 05/13/2016] [Indexed: 11/25/2022] Open
Abstract
The corneal epithelium is maintained by a small pool of tissue stem cells located at the limbus. Through certain injuries or diseases this pool of stem cells may get depleted. This leads to visual impairment. Standard treatment options include autologous or allogeneic limbal stem cell (LSC) transplantation, however graft rejection and chronic inflammation lowers the success rate over long time. Induced pluripotent stem (iPS) cells have opened new possibilities for treating various diseases with patient specific cells, eliminating the risk of immune rejection. In recent years, several protocols have been developed, aimed at the differentiation of iPS cells into the corneal epithelial lineage by mimicking the environmental niche of limbal stem cells. However, the risk of teratoma formation associated with the use of iPS cells hinders most applications from lab into clinics. Here we show that the differentiation of iPS cells into corneal epithelial cells results in the expression of corneal epithelial markers showing a successful differentiation, but the process is long and the level of gene expression for the pluripotency markers does not vanish completely. Therefore we set out to determine a direct transdifferentiation approach to circumvent the intermediate state of pluripotency (iPS-stage). The resulting cells, obtained by direct transdifferentiation of fibroblasts into limbal cells, exhibited corneal epithelial cell morphology and expressed corneal epithelial markers. Hence we shows for the first time a direct transdifferentiation of human dermal fibroblasts into the corneal epithelial lineage that may serve as source for corneal epithelial cells for transplantation approaches.
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Affiliation(s)
- Artur Cieślar-Pobuda
- Stem Cell Group, Nordic EMBL Partnership, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Oslo, Norway.,Institute of Automatic Control, Silesian University of Technology, Gliwice, Poland
| | - Mehrdad Rafat
- LinkoCare Life Sciences AB, Mjärdevi Science Park, Linköping, Sweden
| | - Viktoria Knoflach
- Unit of Molecular Neurobiology, Department of Medical Biochemistry & Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Magdalena Skonieczna
- Institute of Automatic Control, Silesian University of Technology, Gliwice, Poland.,Center for Biotechnology, Bioengineering and Bioinformatics, Silesian University of Technology, Gliwice, Poland
| | | | - Andrzej Małecki
- Laboratory of Molecular Biology, Faculty of Physiotherapy, The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Elżbieta Urasińska
- Department of Pathology, Pomeranian Medical University, Szczecin, Poland
| | - Seaid Ghavami
- Department of Human Anatomy and Cell Science, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Marek J Łos
- LinkoCare Life Sciences AB, Mjärdevi Science Park, Linköping, Sweden.,Laboratory of Molecular Biology, Faculty of Physiotherapy, The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
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128
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Rogerson C, Bergamaschi D, O'Shaughnessy RFL. Uncovering mechanisms of nuclear degradation in keratinocytes: A paradigm for nuclear degradation in other tissues. Nucleus 2018; 9:56-64. [PMID: 29205081 PMCID: PMC5973266 DOI: 10.1080/19491034.2017.1412027] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Eukaryotic nuclei are essential organelles, storing the majority of the cellular DNA, comprising the site of most DNA and RNA synthesis, controlling gene expression and therefore regulating cellular function. The majority of mammalian cells retain their nucleus throughout their lifetime, however, in three mammalian tissues the nucleus is entirely removed and its removal is essential for cell function. Lens fibre cells, erythroblasts and epidermal keratinocytes all lose their nucleus in the terminal differentiation pathways of these cell types. However, relatively little is known about the pathways that lead to complete nuclear removal and about how these pathways are regulated. In this review, we aim to discuss the current understanding of nuclear removal mechanisms in these three cell types and expand upon how recent studies into nuclear degradation in keratinocytes, an easily accessible experimental model, could contribute to a wider understanding of these molecular mechanisms in both health and pathology.
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Affiliation(s)
- Clare Rogerson
- a Centre for Cell Biology and Cutaneous Research , Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London , London , UK
| | - Daniele Bergamaschi
- a Centre for Cell Biology and Cutaneous Research , Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London , London , UK
| | - Ryan F L O'Shaughnessy
- a Centre for Cell Biology and Cutaneous Research , Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London , London , UK
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129
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Hurbain I, Romao M, Sextius P, Bourreau E, Marchal C, Bernerd F, Duval C, Raposo G. Melanosome Distribution in Keratinocytes in Different Skin Types: Melanosome Clusters Are Not Degradative Organelles. J Invest Dermatol 2017; 138:647-656. [PMID: 29054596 DOI: 10.1016/j.jid.2017.09.039] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 09/11/2017] [Accepted: 09/23/2017] [Indexed: 10/18/2022]
Abstract
The melanosome pattern was characterized systematically in keratinocytes in situ in highly, moderately, and lightly pigmented human skin, classified according to the individual typological angle, a colorimetric measure of skin color phenotype. Electron microscopy of skin samples showed qualitatively and quantitatively that in highly pigmented skin, although melanosomes are mostly isolated and distributed throughout the entire epidermis, clusters are also observed in the basal layer. In moderately and lightly pigmented skin, melanosomes are concentrated in the first layer of the epidermis, isolated-but for most of them, grouped as clusters of melanocores delimited by a single membrane. Electron tomography resolving intracellular three-dimensional organization of organelles showed that clustered melanocores depict contacts with other cellular compartments, such as endoplasmic reticulum and mitochondria. Additionally, immunogold labelling showed that clusters of melanocores do not correspond to autophagosomes or melanophagosomes but that they present, similarly to melanosomes in melanocytes, features of nonacidic, nondegradative organelles. Overall, these observations suggest that melanocore clusters do not correspond to autophagic organelles but represent reservoirs or protective structures for melanosome integrity and function. These results open avenues for understanding the basis of skin pigmentation in different skin color phenotypes.
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Affiliation(s)
- Ilse Hurbain
- Institut Curie, Paris Sciences Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Cell and Tissue Imaging Core Facility PICT-IBiSA, Institut Curie, Paris, France
| | - Maryse Romao
- Institut Curie, Paris Sciences Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Cell and Tissue Imaging Core Facility PICT-IBiSA, Institut Curie, Paris, France
| | - Peggy Sextius
- L'Oréal Research and Innovation, Aulnay sous Bois, France
| | | | - Céline Marchal
- L'Oréal Research and Innovation, Aulnay sous Bois, France
| | | | | | - Graça Raposo
- Institut Curie, Paris Sciences Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France.
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130
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Šahmatova L, Sügis E, Šunina M, Hermann H, Prans E, Pihlap M, Abram K, Rebane A, Peterson H, Peterson P, Kingo K, Kisand K. Signs of innate immune activation and premature immunosenescence in psoriasis patients. Sci Rep 2017; 7:7553. [PMID: 28790368 PMCID: PMC5548718 DOI: 10.1038/s41598-017-07975-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 07/03/2017] [Indexed: 12/31/2022] Open
Abstract
Psoriasis is a chronic inflammatory disease that affects skin and is associated with systemic inflammation and many serious comorbidities ranging from metabolic syndrome to cancer. Important discoveries about psoriasis pathogenesis have enabled the development of effective biological treatments blocking the T helper 17 pathway. However, it has not been settled whether psoriasis is a T cell-mediated autoimmune disease or an autoinflammatory disorder that is driven by exaggerated innate immune signalling. Our comparative gene expression and hierarchical cluster analysis reveal important gene circuits involving innate receptors. Innate immune activation is indicated by increased absent in melanoma 2 (AIM2) inflammasome gene expression and active caspase 1 staining in psoriatic lesional skin. Increased eomesodermin (EOMES) expression in lesional and non-lesional skin is suggestive of innate-like virtual memory CD8+ T cell infiltration. We found that signs of systemic inflammation were present in most of the patients, correlated with the severity of the disease, and pointed to IL-6 involvement in the pathogenesis of psoriatic arthritis. Among the circulating T cell subpopulations, we identified a higher proportion of terminally differentiated or senescent CD8+ T cells, especially in patients with long disease duration, suggesting premature immunosenescence and its possible implications for psoriasis co-morbidities.
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Affiliation(s)
- Liisi Šahmatova
- Department of Dermatology, University of Tartu, Tartu, Estonia.,Dermatology Clinic, Tartu University Hospital, Tartu, Estonia
| | - Elena Sügis
- Institute of Computer Science, University of Tartu, Tartu, Estonia.,Quretec Ltd, Tartu, Estonia
| | - Marina Šunina
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Helen Hermann
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Ele Prans
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Maire Pihlap
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Kristi Abram
- Dermatology Clinic, Tartu University Hospital, Tartu, Estonia
| | - Ana Rebane
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Hedi Peterson
- Institute of Computer Science, University of Tartu, Tartu, Estonia.,Quretec Ltd, Tartu, Estonia
| | - Pärt Peterson
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Külli Kingo
- Department of Dermatology, University of Tartu, Tartu, Estonia.,Dermatology Clinic, Tartu University Hospital, Tartu, Estonia
| | - Kai Kisand
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia.
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131
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Phosphoinositide 3-Kinase-Dependent Signalling Pathways in Cutaneous Squamous Cell Carcinomas. Cancers (Basel) 2017; 9:cancers9070086. [PMID: 28696382 PMCID: PMC5532622 DOI: 10.3390/cancers9070086] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/26/2017] [Accepted: 07/03/2017] [Indexed: 01/11/2023] Open
Abstract
Cutaneous squamous cell carcinoma (cSCC) derives from keratinocytes in the epidermis and accounts for 15–20% of all cutaneous malignancies. Although it is usually curable by surgery, 5% of these tumours metastasise leading to poor prognosis mostly because of a lack of therapies and validated biomarkers. As the incidence rate is rising worldwide it has become increasingly important to better understand the mechanisms involved in cSCC development and progression in order to develop therapeutic strategies. Here we discuss some of the evidence indicating that activation of phosphoinositide 3-kinases (PI3Ks)-dependent signalling pathways (in particular the PI3Ks targets Akt and mTOR) has a key role in cSCC. We further discuss available data suggesting that inhibition of these pathways can be beneficial to counteract the disease. With the growing number of different inhibitors currently available, it would be important to further investigate the specific contribution of distinct components of the PI3Ks/Akt/mTOR pathways in order to identify the most promising molecular targets and the best strategy to inhibit cSCC.
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132
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Inflammation dependent mTORC1 signaling interferes with the switch from keratinocyte proliferation to differentiation. PLoS One 2017; 12:e0180853. [PMID: 28700632 PMCID: PMC5507280 DOI: 10.1371/journal.pone.0180853] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 06/06/2017] [Indexed: 12/13/2022] Open
Abstract
Psoriasis is a frequent and often severe inflammatory skin disease, characterized by altered epidermal homeostasis. Since we found previously that Akt/mTOR signaling is hyperactivated in psoriatic skin, we aimed at elucidating the role of aberrant mTORC1 signaling in this disease. We found that under healthy conditions mTOR signaling was shut off when keratinocytes switch from proliferation to terminal differentiation. Inflammatory cytokines (IL-1β, IL-17A, TNF-α) induced aberrant mTOR activity which led to enhanced proliferation and reduced expression of differentiation markers. Conversely, regular differentiation could be restored if mTORC1 signaling was blocked. In mice, activation of mTOR through the agonist MHY1485 also led to aberrant epidermal organization and involucrin distribution. In summary, these results not only identify mTORC1 as an important signal integrator pivotal for the cells fate to either proliferate or differentiate, but emphasize the role of inflammation-dependent mTOR activation as a psoriatic pathomechanism.
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133
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Anding AL, Baehrecke EH. Cleaning House: Selective Autophagy of Organelles. Dev Cell 2017; 41:10-22. [PMID: 28399394 DOI: 10.1016/j.devcel.2017.02.016] [Citation(s) in RCA: 414] [Impact Index Per Article: 59.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 12/12/2016] [Accepted: 02/16/2017] [Indexed: 10/19/2022]
Abstract
The selective clearance of organelles by autophagy is critical for the regulation of cellular homeostasis in organisms from yeast to humans. Removal of damaged organelles clears the cell of potentially toxic byproducts and enables reuse of organelle components for bioenergetics. Thus, defects in organelle clearance may be detrimental to the health of the cells, contributing to cancer, neurodegeneration, and inflammatory diseases. Organelle-specific autophagy can clear mitochondria, peroxisomes, lysosomes, ER, chloroplasts, and the nucleus. Here, we review our understanding of the mechanisms that regulate the clearance of organelles by autophagy and highlight gaps in our knowledge of these processes.
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Affiliation(s)
- Allyson L Anding
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Eric H Baehrecke
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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134
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Ueki M, Takeshita H, Utsunomiya N, Chino T, Oyama N, Hasegawa M, Kimura-Kataoka K, Fujihara J, Iida R, Yasuda T. Survey of single-nucleotide polymorphisms in the gene encoding human deoxyribonuclease I-like 2 producing loss of function potentially implicated in the pathogenesis of parakeratosis. PLoS One 2017; 12:e0175083. [PMID: 28394916 PMCID: PMC5386265 DOI: 10.1371/journal.pone.0175083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/20/2017] [Indexed: 11/19/2022] Open
Abstract
Dysfunction of DNase I-like 2 (DNase 1L2) has been assumed to play a role in the etiology of parakeratosis through incomplete degradation of DNA in the epidermis. However, the pathogenetic background factor for such pathophysiologic conditions remains unknown. In this context, non-synonymous single-nucleotide polymorphisms (SNPs) in DNASE1L2 that would potentially result in loss of in vivo DNase 1L2 activity might serve as a genetic risk factor for such pathophysiologic conditions. Our aim was to effectively survey the non-synonymous SNPs of DNASE1L2 that would produce a loss-of-function variant of the enzyme together with a genetic distribution in the various populations. Here, the effects of all of the SNPs predicted by PolyPhen-2 analysis to be "probably damaging" (score = 1.000), and derived from frameshift/nonsense mutations, on the activity of DNase 1L2 were examined using the corresponding DNase 1L2 variants expressed in COS-7 cells. Genotyping of these SNPs was also performed in three ethnic groups including 14 different populations. Among the 28 SNPs examined, the minor allele of 23 SNPs was defined as a loss-of-function variant resulting in loss of DNase 1L2 function, indicating that Polyphen-2 analysis could be effective for surveys of at least non-synonymous SNPs resulting in loss of function. On the other hand, these minor alleles were not distributed worldwide, thereby avoiding any marked reduction of the enzyme activity in human populations. Furthermore, all of the 19 SNPs originating from frameshift/ nonsense mutations found in DNASE1L2 resulted in loss of function of the enzyme. Thus, the present findings suggest that each of the minor alleles for these SNPs may serve as one of genetic risk factors for parakeratotic skin diseases such as psoriasis, even though they lack a worldwide genetic distribution.
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Affiliation(s)
- Misuzu Ueki
- Department of Medical Genetics and Biochemistry, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan
| | - Haruo Takeshita
- Department of Legal Medicine, Shimane University School of Medicine, Enya, Izumo, Japan
| | - Natsuko Utsunomiya
- Department of Dermatology, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan
| | - Takanao Chino
- Department of Dermatology, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan
| | - Noritaka Oyama
- Department of Dermatology, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan
| | - Minoru Hasegawa
- Department of Dermatology, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan
| | - Kaori Kimura-Kataoka
- Department of Legal Medicine, Shimane University School of Medicine, Enya, Izumo, Japan
| | - Junko Fujihara
- Department of Legal Medicine, Shimane University School of Medicine, Enya, Izumo, Japan
| | - Reiko Iida
- Department of Life Sciences, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan
| | - Toshihiro Yasuda
- Department of Medical Genetics and Biochemistry, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan
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135
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Impact on Autophagy and Ultraviolet B Induced Responses of Treatment with the MTOR Inhibitors Rapamycin, Everolimus, Torin 1, and pp242 in Human Keratinocytes. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:5930639. [PMID: 28400912 PMCID: PMC5376460 DOI: 10.1155/2017/5930639] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/15/2017] [Accepted: 02/13/2017] [Indexed: 12/21/2022]
Abstract
The mechanistic target of Rapamycin (MTOR) protein is a crucial signaling regulator in mammalian cells that is extensively involved in cellular biology. The function of MTOR signaling in keratinocytes remains unclear. In this study, we detected the MTOR signaling and autophagy response in the human keratinocyte cell line HaCaT and human epidermal keratinocytes treated with MTOR inhibitors. Moreover, we detected the impact of MTOR inhibitors on keratinocytes exposed to the common carcinogenic stressors ultraviolet B (UVB) and UVA radiation. As a result, keratinocytes were sensitive to the MTOR inhibitors Rapamycin, everolimus, Torin 1, and pp242, but the regulation of MTOR downstream signaling was distinct. Next, autophagy induction only was observed in HaCaT cells treated with Rapamycin. Furthermore, we found that MTOR signaling was insensitive to UVB but sensitive to UVA radiation. UVB treatment also had no impact on the inhibition of MTOR signaling by MTOR inhibitors. Finally, MTOR inhibition by Rapamycin, everolimus, or pp242 did not affect the series of biological events in keratinocytes exposed to UVB, including the downregulation of BiP and PERK, activation of Histone H2A and JNK, and cleavage of caspase-3 and PARP. Our study demonstrated that MTOR inhibition in keratinocytes cannot always induce autophagy, and the MTOR pathway does not play a central role in the UVB triggered cellular response.
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136
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The trisaccharide raffinose modulates epidermal differentiation through activation of liver X receptor. Sci Rep 2017; 7:43823. [PMID: 28266648 PMCID: PMC5339792 DOI: 10.1038/srep43823] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 02/01/2017] [Indexed: 12/19/2022] Open
Abstract
The epidermal barrier function requires optimal keratinocyte differentiation and epidermal lipid synthesis. Liver X receptor (LXR) α and β, are important transcriptional regulators of the epidermal gene expression. Here, we show that raffinose, a ubiquitously present trisaccharide in plants, activated the transcriptional activity of LXRα/β, which led to the induction of genes required for keratinocyte differentiation such as involucrin and filaggrin, and genes involved in lipid metabolism and transport including SCD1 and ABCA1 in both HaCaT and normal human epidermal keratinocytes. Raffinose induced the expression of JunD and Fra1, and their DNA binding in the AP1 motif in the promoters of involucrin and loricrin. Interestingly, LXR bound the AP1 motif upon raffinose treatment, and conversely, JunD and Fra1 bound the LXR response element in promoters of LXR target genes, which indicates the presence of a postive cross-talk between LXR and AP1 in the regualtion of these genes. Finally, the effect of raffinose in epidermal barrier function was confirmed by applying raffinose in an ointment formulation to the skin of hairless mice. These findings suggest that raffinose could be examined as an ingredient in functional cosmetics and therapeutic agents for the treatment of cutaneous disorders associated with abnormal epidermal barrier function.
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137
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Fischer H, Fumicz J, Rossiter H, Napirei M, Buchberger M, Tschachler E, Eckhart L. Holocrine Secretion of Sebum Is a Unique DNase2-Dependent Mode of Programmed Cell Death. J Invest Dermatol 2017; 137:587-594. [PMID: 27771328 DOI: 10.1016/j.jid.2016.10.017] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 09/30/2016] [Accepted: 10/03/2016] [Indexed: 12/11/2022]
Abstract
Sebaceous glands produce sebum via holocrine secretion, a largely uncharacterized mode of programmed cell death that contributes to the homeostasis and barrier function of the skin. To determine the mechanism of DNA degradation during sebocyte cell death, we have inactivated candidate DNA-degrading enzymes by targeted gene deletions in mice. DNase1 and DNase1-like 2 were dispensable for nuclear DNA degradation in sebocytes. By contrast, epithelial cell-specific deletion of lysosomal DNase2 blocked DNA degradation in these cells. DNA breakdown during sebocyte differentiation coincided with the loss of LAMP1 and was accelerated by the abrogation of autophagy, the central cellular program of lysosome-dependent catabolism. Suppression of DNA degradation by the deletion of DNase2 resulted in aberrantly increased concentrations of residual DNA and decreased amounts of the DNA metabolite uric acid in secreted sebum. These results define holocrine secretion as a DNase2-mediated form of programmed cell death and suggest that autophagy-dependent metabolism, DNA degradation, and the molecular composition of sebum are mechanistically linked.
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Affiliation(s)
- Heinz Fischer
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Judith Fumicz
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Heidemarie Rossiter
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Markus Napirei
- Department of Anatomy and Molecular Embryology, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| | - Maria Buchberger
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Erwin Tschachler
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Leopold Eckhart
- Research Division of Biology and Pathobiology of the Skin, Department of Dermatology, Medical University of Vienna, Vienna, Austria.
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138
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Peng H, Park JK, Lavker RM. Autophagy and Macropinocytosis: Keeping an Eye on the Corneal/Limbal Epithelia. Invest Ophthalmol Vis Sci 2017; 58:416-423. [PMID: 28118670 PMCID: PMC5270618 DOI: 10.1167/iovs.16-21111] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 12/05/2016] [Indexed: 02/07/2023] Open
Abstract
Autophagy and macropinocytosis are processes that are vital for cellular homeostasis, and help cells respond to stress and take up large amounts of material, respectively. The limbal and corneal epithelia have the machinery necessary to carry out both processes; however, autophagy and macropinocytosis are relatively understudied in these two epithelia. In this Perspectives, we describe the basic principles behind macropinocytosis and autophagy, discuss how these two processes are regulated in the limbal and corneal epithelia, consider how these two processes impact on the physiology of limbal and corneal epithelia, and elaborate on areas of future research in autophagy and macropinocytosis as related to the limbal/corneal epithelia.
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Affiliation(s)
- Han Peng
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States
| | - Jong Kook Park
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States
| | - Robert M. Lavker
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States
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Luo M, Zhao X, Song Y, Cheng H, Zhou R. Nuclear autophagy: An evolutionarily conserved mechanism of nuclear degradation in the cytoplasm. Autophagy 2016; 12:1973-1983. [PMID: 27541589 DOI: 10.1080/15548627.2016.1217381] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Macroautophagy/autophagy is a catabolic process that is essential for cellular homeostasis. Studies on autophagic degradation of cytoplasmic components have generated interest in nuclear autophagy. Although its mechanisms and roles have remained elusive, tremendous progress has been made toward understanding nuclear autophagy. Nuclear autophagy is evolutionarily conserved in eukaryotes that may target various nuclear components through a series of processes, including nuclear sensing, nuclear export, autophagic substrate encapsulation and autophagic degradation in the cytoplasm. However, the molecular processes and regulatory mechanisms involved in nuclear autophagy remain largely unknown. Numerous studies have highlighted the importance of nuclear autophagy in physiological and pathological processes such as cancer. This review focuses on current advances in nuclear autophagy and provides a summary of its research history and landmark discoveries to offer new perspectives.
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Affiliation(s)
- Majing Luo
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
| | - Xueya Zhao
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
| | - Ying Song
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
| | - Hanhua Cheng
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
| | - Rongjia Zhou
- a Hubei Key Laboratory of Cell Homeostasis, Laboratory of Molecular and Developmental Genetics, College of Life Sciences , Wuhan University , Wuhan , China
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140
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Nucleophagy: A New Look at Past Observations. J Invest Dermatol 2016; 136:1316-1318. [PMID: 27155459 DOI: 10.1016/j.jid.2016.04.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 04/22/2016] [Accepted: 04/23/2016] [Indexed: 12/18/2022]
Abstract
Keratinization of the stratum corneum involves a highly choreographed sequence of events in which granular cells lose their nuclei and become desiccated corneocytes. Akinduro et al. detail the molecular machinery underlying removal of the nucleus (nucleophagy) during the final stages of keratinization. They provide evidence that nucleophagy is induced when the keratinocytes differentiate and that failure in the initiation of nucleophagy is associated with parakeratosis.
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