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1.
J Forensic Sci ; 66(1): 202-208, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33136290

RESUMO

Adermatoglyphia is a very rare autosomal-dominant condition that is genetically inherited and causes an individual to be born without conventional ridge detail on either their palmar or plantar surfaces (the fingers and palms of the hands and the toes and the soles of the feet). While adermatoglyphia has been the focus of medical and genetic research, no previous research has been conducted with regard to the forensic recovery and identification of marks from an adermatoglyphic individual. By observation of ridge detail donated by an adermatoglyphic subject, the study uses different methods in order to capture fingermarks (methods include: inked capture, livescan (biometric) capture, cyanoacrylate fuming, ninhydrin enhancement, and physical developer). Unusually, the purpose of this paper ends up presenting a number of examples of an absence of evidence; unsuccessful attempts made to capture and enhance fingerprint ridge detail. This is determined over a range of standard means including "live" donations by the adermatoglyphic subject onto the Livescan system, and enhancements of latent donations. The subject shows to leave either insubstantial fingermarks with no detail, or no mark whatsoever.


Assuntos
Dermatoglifia , Epiderme/anormalidades , Cianoacrilatos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Tinta , Ninidrina , Volatilização
2.
J Cell Biol ; 218(4): 1390-1406, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30867227

RESUMO

Development of the skin epidermis requires tight spatiotemporal control over the activity of several signaling pathways; however, the mechanisms that orchestrate these events remain poorly understood. Here, we identify a key role for the Wave complex proteins ABI1 and Wave2 in regulating signals that control epidermal shape and growth. In utero RNAi-mediated silencing of Abi1 or Wasf2 induced cellular hyperproliferation and defects in architecture of the interfollicular epidermis (IFE) and delayed hair follicle growth. Unexpectedly, SOX9, a hair follicle growth regulator, was aberrantly expressed throughout the IFE of the mutant embryos, and its forced overexpression mimicked the Wave complex loss-of-function phenotype. Moreover, Wnt signaling, which regulates SOX9+ cell specification, was up-regulated in Wave complex loss-of-function IFE. Importantly, we show that the Wave complex regulates filamentous actin content and that a decrease in actin levels is sufficient to elevate Wnt/ß-catenin signaling. Our results identify a novel role for Wave complex- and actin-regulated signaling via Wnt and SOX9 in skin development.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proliferação de Células , Proteínas do Citoesqueleto/metabolismo , Epiderme/metabolismo , Queratinócitos/metabolismo , Fatores de Transcrição SOX9/metabolismo , Família de Proteínas da Síndrome de Wiskott-Aldrich/metabolismo , Via de Sinalização Wnt , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Células Cultivadas , Proteínas do Citoesqueleto/genética , Epiderme/anormalidades , Regulação da Expressão Gênica no Desenvolvimento , Inativação Gênica , Folículo Piloso/anormalidades , Folículo Piloso/metabolismo , Camundongos , Morfogênese , Fosforilação , Fatores de Transcrição SOX9/genética , Família de Proteínas da Síndrome de Wiskott-Aldrich/genética , beta Catenina/metabolismo
3.
Sci Rep ; 7: 44828, 2017 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-28317864

RESUMO

The epidermis, which consists mainly of keratinocytes, acts as a physical barrier to infections by regulating keratinocyte proliferation and differentiation. Hair follicles undergo continuous cycling to produce new one. Therefore, optimum supply of energy from the mitochondria is essential for maintaining skin homeostasis and hair growth. CRIF1 is a mitochondrial protein that regulates mitoribosome-mediated synthesis and insertion of mitochondrial oxidative phosphorylation polypeptides into the mitochondrial membrane in mammals. Recent studies reveal that conditional knockout (cKO) of Crif1 in specific tissues of mice induced mitochondrial dysfunction. To determine whether the mitochondrial function of keratinocytes affects skin homeostasis and hair morphogenesis, we generated epidermis-specific Crif1 cKO mice. Deletion of Crif1 in epidermis resulted in impaired mitochondrial function and Crif1 cKO mice died within a week. Keratinocyte proliferation and differentiation were markedly inhibited in Crif1 cKO mice. Furthermore, hair follicle morphogenesis of Crif1 cKO mice was disrupted by down-regulation of Wnt/ß-catenin signaling. These results demonstrate that mitochondrial function in keratinocytes is essential for maintaining epidermal homeostasis and hair follicle morphogenesis.


Assuntos
Proteínas de Ciclo Celular/deficiência , Epiderme/metabolismo , Deleção de Genes , Cabelo/anormalidades , Morfogênese/genética , Anormalidades da Pele/genética , Animais , Apoptose/genética , Proliferação de Células , Epiderme/anormalidades , Marcação de Genes , Homeostase , Queratinócitos/metabolismo , Queratinócitos/patologia , Queratinócitos/ultraestrutura , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Via de Sinalização Wnt
4.
J Pathol ; 239(3): 374-83, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27126290

RESUMO

The epidermis is the outermost layer of skin that acts as a barrier to protect the body from the external environment and to control water and heat loss. This barrier function is established through the multistage differentiation of keratinocytes and the presence of bioactive sphingolipids such as ceramides, the levels of which are tightly regulated by a balance of ceramide synthase and ceramidase activities. Here we reveal the essential role of alkaline ceramidase 1 (Acer1) in the skin. Acer1-deficient (Acer1(-/-) ) mice showed elevated levels of ceramide in the skin, aberrant hair shaft cuticle formation and cyclic alopecia. We demonstrate that Acer1 is specifically expressed in differentiated interfollicular epidermis, infundibulum and sebaceous glands and consequently Acer1(-/-) mice have significant alterations in infundibulum and sebaceous gland architecture. Acer1(-/-) skin also shows perturbed hair follicle stem cell compartments. These alterations result in Acer1(-/-) mice showing increased transepidermal water loss and a hypermetabolism phenotype with associated reduction of fat content with age. We conclude that Acer1 is indispensable for mammalian skin homeostasis and whole-body energy homeostasis. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Ceramidase Alcalina/metabolismo , Alopecia/enzimologia , Ceramidas/metabolismo , Metabolismo Energético , Homeostase , Ceramidase Alcalina/genética , Alopecia/fisiopatologia , Animais , Diferenciação Celular , Epiderme/anormalidades , Epiderme/enzimologia , Feminino , Folículo Piloso/anormalidades , Folículo Piloso/enzimologia , Humanos , Queratinócitos/enzimologia , Queratinócitos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hipófise/anormalidades , Hipófise/enzimologia , Glândulas Sebáceas/anormalidades , Glândulas Sebáceas/enzimologia , Pele/enzimologia , Anormalidades da Pele , Esfingolipídeos/metabolismo
5.
J Biol Chem ; 291(6): 3030-42, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26601958

RESUMO

UBE2W ubiquitinates N termini of proteins rather than internal lysine residues, showing a preference for substrates with intrinsically disordered N termini. The in vivo functions of this intriguing E2, however, remain unknown. We generated Ube2w germ line KO mice that proved to be susceptible to early postnatal lethality without obvious developmental abnormalities. Although the basis of early death is uncertain, several organ systems manifest changes in Ube2w KO mice. Newborn Ube2w KO mice often show altered epidermal maturation with reduced expression of differentiation markers. Mirroring higher UBE2W expression levels in testis and thymus, Ube2w KO mice showed a disproportionate decrease in weight of these two organs (~50%), suggesting a functional role for UBE2W in the immune and male reproductive systems. Indeed, Ube2w KO mice displayed sustained neutrophilia accompanied by increased G-CSF signaling and testicular vacuolation associated with decreased fertility. Proteomic analysis of a vulnerable organ, presymptomatic testis, showed a preferential accumulation of disordered proteins in the absence of UBE2W, consistent with the view that UBE2W preferentially targets disordered polypeptides. These mice further allowed us to establish that UBE2W is ubiquitously expressed as a single isoform localized to the cytoplasm and that the absence of UBE2W does not alter cell viability in response to various stressors. Our results establish that UBE2W is an important, albeit not essential, protein for early postnatal survival and normal functioning of multiple organ systems.


Assuntos
Epiderme , Anormalidades da Pele , Enzimas de Conjugação de Ubiquitina , Animais , Epiderme/anormalidades , Epiderme/enzimologia , Epiderme/imunologia , Transtornos Leucocíticos/congênito , Transtornos Leucocíticos/enzimologia , Transtornos Leucocíticos/genética , Transtornos Leucocíticos/imunologia , Masculino , Camundongos , Camundongos Knockout , Anormalidades da Pele/enzimologia , Anormalidades da Pele/genética , Anormalidades da Pele/imunologia , Testículo/enzimologia , Testículo/imunologia , Timo/enzimologia , Timo/imunologia , Enzimas de Conjugação de Ubiquitina/deficiência , Enzimas de Conjugação de Ubiquitina/imunologia
6.
Am J Pathol ; 185(4): 1012-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25660180

RESUMO

Although keratosis pilaris (KP) is common, its etiopathogenesis remains unknown. KP is associated clinically with ichthyosis vulgaris and atopic dermatitis and molecular genetically with filaggrin-null mutations. In 20 KP patients and 20 matched controls, we assessed the filaggrin and claudin 1 genotypes, the phenotypes by dermatoscopy, and the morphology by light and transmission electron microscopy. Thirty-five percent of KP patients displayed filaggrin mutations, demonstrating that filaggrin mutations only partially account for the KP phenotype. Major histologic and dermatoscopic findings of KP were hyperkeratosis, hypergranulosis, mild T helper cell type 1-dominant lymphocytic inflammation, plugging of follicular orifices, striking absence of sebaceous glands, and hair shaft abnormalities in KP lesions but not in unaffected skin sites. Changes in barrier function and abnormal paracellular permeability were found in both interfollicular and follicular stratum corneum of lesional KP, which correlated ultrastructurally with impaired extracellular lamellar bilayer maturation and organization. All these features were independent of filaggrin genotype. Moreover, ultrastructure of corneodesmosomes and tight junctions appeared normal, immunohistochemistry for claudin 1 showed no reduction in protein amounts, and molecular analysis of claudin 1 was unremarkable. Our findings suggest that absence of sebaceous glands is an early step in KP pathogenesis, resulting in downstream hair shaft and epithelial barrier abnormalities.


Assuntos
Anormalidades Múltiplas/patologia , Doença de Darier/patologia , Epiderme/anormalidades , Sobrancelhas/anormalidades , Cabelo/anormalidades , Proteínas de Filamentos Intermediários/deficiência , Glândulas Sebáceas/anormalidades , Anormalidades Múltiplas/genética , Adulto , Idoso , Claudina-1/metabolismo , Doença de Darier/genética , Dermoscopia , Desmossomos/metabolismo , Epiderme/ultraestrutura , Sobrancelhas/patologia , Feminino , Proteínas Filagrinas , Genótipo , Cabelo/ultraestrutura , Humanos , Proteínas de Filamentos Intermediários/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Permeabilidade , Fenótipo , Glândulas Sebáceas/patologia , Glândulas Sebáceas/ultraestrutura , Adulto Jovem
7.
Histochem Cell Biol ; 143(5): 481-96, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25366125

RESUMO

Mice with skin and hair follicle (HF) defects are common models of human skin disorders. A mutant strain with the we/we wal/wal genotype develops alopecia. We found the hair shaft structure in the pelage of mutant mice to have significant defects. Although these mice lose their hair at 21 days, a label-retaining cell population persists in HFs until at least day 54. Depilation-induced anagen was accomplished in we/we wal/wal mutants but the resulting hair shafts were short and extremely deformed. Serious abnormalities in epidermis stratification and HF morphogenesis exist in we/we wal/wal homozygous E18.5 embryos. There were significantly fewer HF primordia in this mutant compared with wild type. We discovered specific structures, identified as invalid placodes, positive for ectodysplasin A1 receptor, nuclear ß-catenin, and LEF1, which failed to invaginate, produced a double basal-like layer of epidermal cells, and lacked cylindrical keratinocytes. Specification of dermal papillae (DP) was impaired, and the papillary dermis expressed alkaline phosphatase and LEF1. We also detected DP-like groups of intensively stained cells in the absence of visible signs of folliculogenesis in the epidermis. We showed differentiation disturbances in the mutant embryonic E18.5 epidermis and HFs: The cornified layer was absent, the width of the spinous layer was reduced, and HFs lacked LEF1-positive precortex cells. In this study, we used a very interesting and useful mouse model of alopecia. The presence of symptoms of skin disorders in we/we wal/wal murine embryos correlates with the postnatal skin phenotype. This correlation may help to evaluate reasons of alopecia.


Assuntos
Alopecia/patologia , Epiderme/anormalidades , Folículo Piloso/anormalidades , Fatores Etários , Alopecia/embriologia , Alopecia/genética , Alopecia/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Receptor Edar/metabolismo , Epiderme/metabolismo , Genótipo , Idade Gestacional , Folículo Piloso/metabolismo , Remoção de Cabelo , Queratinócitos/metabolismo , Queratinócitos/patologia , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Morfogênese , Fenótipo , beta Catenina/metabolismo
8.
J Invest Dermatol ; 134(1): 24-32, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23792463

RESUMO

Histone deacetylases (HDACs) are present in the epidermal layer of the skin, outer root sheath, and hair matrix. To investigate how histone acetylation affects skin morphogenesis and homeostasis, mice were generated with a K14 promoter-mediated reduction of Hdac1 or Hdac2. The skin of HDAC1 null (K14-Cre Hdac1(cKO/cKO)) mice exhibited a spectrum of lesions, including irregularly thickened interfollicular epidermis, alopecia, hair follicle dystrophy, claw dystrophy, and abnormal pigmentation. Hairs are sparse, short, and intermittently coiled. The distinct pelage hair types are lost. During the first hair cycle, hairs are lost and replaced by dystrophic hair follicles with dilated infundibulae. The dystrophic hair follicle epithelium is stratified and is positive for K14, involucrin, and TRP63, but negative for keratin 10. Some dystrophic follicles are K15 positive, but mature hair fiber keratins are absent. The digits form extra hyperpigmented claws on the lateral sides. Hyperpigmentation is observed in the interfollicular epithelium, the tail, and the feet. Hdac1 and Hdac2 dual transgenic mice (K14-Cre Hdac1(cKO/cKO) Hdac2(+/cKO)) have similar but more obvious abnormalities. These results show that suppression of epidermal HDAC activity leads to improper ectodermal organ morphogenesis and disrupted hair follicle regeneration and homeostasis, as well as indirect effects on pigmentation.


Assuntos
Anormalidades Múltiplas/genética , Ectoderma/anormalidades , Histona Desacetilase 1/genética , Histona Desacetilase 2/genética , Morfogênese/genética , Anormalidades Múltiplas/patologia , Alopecia/genética , Animais , Epiderme/anormalidades , Folículo Piloso/anormalidades , Homeostase/genética , Queratinas/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Unhas Malformadas/genética , Unhas Malformadas/patologia , Deleção de Sequência , Pigmentação da Pele/genética
10.
Mol Cell Biol ; 33(14): 2787-96, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23689133

RESUMO

The sphingolipid backbone ceramide (Cer) is a major component of lipid lamellae in the stratum corneum of epidermis and has a pivotal role in epidermal barrier formation. Unlike Cers in other tissues, Cers in epidermis contain extremely long fatty acids (FAs). Decreases in epidermal Cer levels, as well as changes in their FA chain lengths, cause several cutaneous disorders. However, the molecular mechanisms that produce such extremely long Cers and determine their chain lengths are poorly understood. We generated mice deficient in the Elovl1 gene, which encodes the FA elongase responsible for producing C20 to C28 FAs. Elovl1 knockout mice died shortly after birth due to epidermal barrier defects. The lipid lamellae in the stratum corneum were largely diminished in these mice. In the epidermis of the Elovl1-null mice, the levels of Cers with ≥C26 FAs were decreased, while those of Cers with ≤C24 FAs were increased. In contrast, the levels of C24 sphingomyelin were reduced, accompanied by an increase in C20 sphingomyelin levels. Two ceramide synthases, CerS2 and CerS3, expressed in an epidermal layer-specific manner, regulate Elovl1 to produce acyl coenzyme As with different chain lengths. Elovl1 is a key determinant of epidermal Cer chain length and is essential for permeability barrier formation.


Assuntos
Acetiltransferases/genética , Epiderme/enzimologia , Ácidos Graxos/metabolismo , Acetiltransferases/deficiência , Animais , Ceramidas/metabolismo , Grânulos Citoplasmáticos/metabolismo , Epiderme/anormalidades , Epiderme/patologia , Elongases de Ácidos Graxos , Feminino , Genes Letais , Células HEK293 , Humanos , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Permeabilidade , Esfingosina N-Aciltransferase/metabolismo
11.
J Dermatol Sci ; 70(1): 12-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23433550

RESUMO

BACKGROUND: Tight junctions (TJs) contribute to the epithelial barrier function by preventing leakage of solutes through the intercellular space. In the skin, TJs occur in the stratum granulosum (SG), where claudin-1 and claudin-4 are expressed as adhesion molecules of TJs. Claudin-1-deficient (Cldn1(-/-)) mice die within one day of birth accompanied by excessive transepidermal water loss, indicating a critical role of TJs in the epidermal barrier function. However, it has been debated whether the impaired TJ function in the SG also affects the stratum corneum (SC) barrier function or whether it results in skin barrier defects despite a normal SC barrier. OBJECTIVE: To clarify whether the impaired TJ function affects the SC barrier function in Cldn1(-/-) mice. METHODS: The morphology, barrier function and biochemical characteristic of the SC were compared between Cldn1(-/-) and Cldn1(+/+) mice. RESULTS: Scanning electron microscopy demonstrated abnormally wrinkled and rough corneocytes in Cldn1(-/-) mice. Notably, the X-gal tracer easily permeated into the Cldn1(-/-) SC, and water evaporation through isolated Cldn1(-/-) SC sheets was significantly higher than that through Cldn1(+/+) SC sheets. Furthermore, the ceramide composition of the SC lipids and filaggrin processing were altered in Cldn1(-/-) mice. CONCLUSION: Cldn1(-/-) mice exhibited the abnormal SC formation and SC barrier defects. These findings demonstrate for the first time that TJs in the SG play crucial roles in the complete SC formation and SC barrier function.


Assuntos
Claudina-1/genética , Epiderme/anormalidades , Epiderme/metabolismo , Junções Íntimas/metabolismo , Animais , Animais Recém-Nascidos , Água Corporal/metabolismo , Desidratação/genética , Desidratação/metabolismo , Desidratação/patologia , Epiderme/patologia , Feminino , Metabolismo dos Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Varredura , Junções Íntimas/patologia , Junções Íntimas/ultraestrutura , Perda Insensível de Água/genética
12.
Arq. bras. med. vet. zootec ; 65(1): 301-307, fev. 2013. tab
Artigo em Inglês | LILACS | ID: lil-667570

RESUMO

Diflubenzuron (DFB) is used to control ectoparasitic infestation by inhibiting larvae development in the manure and feces of treated animals. It is also currently been used to control tick infestations. In this study, milk and tissues from cattle treated orally with DFB for a 77-120 day period with a commercial product containing the compound were analyzed for the presence of residues. DFB residues were determined by using extraction with acetonitrile, cleanup with C18 SPE and chromatographic analysis by HPLC with UV detection (254nm). DFB was not detected in any of the analysed samples (<0.006mg kg-1 for fat, <0.014mg kg-1 for muscle, <0.015mg kg-1 for kidney, <0.016mg kg-1 for liver and <0.0006mg kg-1 for milk). In this manner, the use of this compound, according to the manufacturer's suggested doses may result in cattle milk, liver, kidneys, fat and muscles being considered safe regarding the presence of DFB residues.


O diflubenzuron (DFB) é um inibidor de desenvolvimento de insetos que inibe a síntese de quitina com atividade ovicida e larvicida e está sendo utilizado na pecuária para o controle do carrapato. Leite e tecidos provenientes de bovinos tratados por um período de 77 a 120 dias com um produto comercial contendo DFB foram analisados quanto à presença de resíduos. Os resíduos de DFB foram determinados utilizando-se extração com acetonitrila, limpeza por SPE C18 e cromatografia líquida de alta eficiência com detecção por UV (254nm). DFB não foi detectado em nenhuma das amostras analisadas (<0.006mg kg-1 para gordura, <0,014mg kg-1 para músculo, <0,015mg kg-1 para rim, <0,016mg kg-1 para fígado e <0.0006mg kg-1 para leite). Dessa forma, a utilização do princípio ativo conforme recomendado pelo fabricante e em níveis suficientes para se obter o efeito larvicida desejado deve resultar em leite, fígado, rins, gordura e músculos que podem ser considerados seguros para o consumo em termos da presença DFB.


Assuntos
Animais , Bovinos , Diflubenzuron/administração & dosagem , Diflubenzuron/química , Diflubenzuron/síntese química , Epiderme/anormalidades , Epiderme , Insetos/citologia , Insetos/química
13.
PLoS One ; 7(11): e47842, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23139756

RESUMO

Birt-Hogg-Dube (BHD) is a tumor suppressor gene syndrome associated with fibrofolliculomas, cystic lung disease, and chromophobe renal cell carcinoma. In seeking to elucidate the pathogenesis of BHD, we discovered a physical interaction between folliculin (FLCN), the protein product of the BHD gene, and p0071, an armadillo repeat containing protein that localizes to the cytoplasm and to adherens junctions. Adherens junctions are one of the three cell-cell junctions that are essential to the establishment and maintenance of the cellular architecture of all epithelial tissues. Surprisingly, we found that downregulation of FLCN leads to increased cell-cell adhesion in functional cell-based assays and disruption of cell polarity in a three-dimensional lumen-forming assay, both of which are phenocopied by downregulation of p0071. These data indicate that the FLCN-p0071 protein complex is a negative regulator of cell-cell adhesion. We also found that FLCN positively regulates RhoA activity and Rho-associated kinase activity, consistent with the only known function of p0071. Finally, to examine the role of Flcn loss on cell-cell adhesion in vivo, we utilized keratin-14 cre-recombinase (K14-cre) to inactivate Flcn in the mouse epidermis. The K14-Cre-Bhd(flox/flox) mice have striking delays in eyelid opening, wavy fur, hair loss, and epidermal hyperplasia with increased levels of mammalian target of rapamycin complex 1 (mTORC1) activity. These data support a model in which dysregulation of the FLCN-p0071 interaction leads to alterations in cell adhesion, cell polarity, and RhoA signaling, with broad implications for the role of cell-cell adhesion molecules in the pathogenesis of human disease, including emphysema and renal cell carcinoma.


Assuntos
Junções Aderentes/metabolismo , Placofilinas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Cateninas/metabolismo , Adesão Celular , Linhagem Celular , Movimento Celular , Desmossomos/metabolismo , Cães , Epiderme/anormalidades , Epiderme/metabolismo , Epiderme/patologia , Cabelo/anormalidades , Cabelo/metabolismo , Cabelo/patologia , Humanos , Integrases/metabolismo , Queratina-14/metabolismo , Camundongos , Modelos Biológicos , Ligação Proteica , Proteínas Proto-Oncogênicas/deficiência , Proteínas Proto-Oncogênicas/genética , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética , Cicatrização , Proteína da Zônula de Oclusão-1/metabolismo , gama Catenina/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , delta Catenina
14.
Am J Pathol ; 181(4): 1180-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22846721

RESUMO

CD109, a glycosylphosphatidylinositol-anchored glycoprotein, is highly expressed in several types of human cancer tissues, in particular, squamous cell carcinomas. In normal human tissues, human CD109 expression is limited to certain cell types including myoepithelial cells of the mammary, lacrimal, salivary, and bronchial glands and basal cells of the prostate and bronchial epithelium. Although CD109 has been reported to negatively regulate transforming growth factor-ß signaling in keratinocytes in vitro, its physiologic role in vivo remains largely unknown. To investigate the function of CD109 in vivo, we generated CD109-deficient (CD109(-/-)) mice. Although CD109(-/-) mice were born normally, transient impairment of hair growth was observed. At histologic analysis, kinked hair shafts, ectatic hair follicles with an accumulation of sebum, and persistent hyperplasia of the epidermis and sebaceous glands were observed in CD109(-/-) mice. Immunohistochemical analysis revealed thickening of the basal and suprabasal layers in the epidermis of CD109(-/-) mice, which is where endogenous CD109 is expressed in wild-type mice. Although CD109 was reported to negatively regulate transforming growth factor-ß signaling, no significant difference in levels of Smad2 phosphorylation was observed in the epidermis between wild-type and CD109(-/-) mice. Instead, Stat3 phosphorylation levels were significantly elevated in the epidermis of CD109(-/-) mice compared with wild-type mice. These results suggest that CD109 regulates differentiation of keratinocytes via a signaling pathway involving Stat3.


Assuntos
Antígenos CD/metabolismo , Epiderme/anormalidades , Epiderme/patologia , Proteínas de Neoplasias/deficiência , Proteínas de Neoplasias/metabolismo , Animais , Epiderme/metabolismo , Técnicas de Introdução de Genes , Marcação de Genes , Cabelo/crescimento & desenvolvimento , Cabelo/metabolismo , Humanos , Hiperplasia , Masculino , Camundongos , Camundongos Knockout , Fosforilação , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Testículo/metabolismo , Fator de Crescimento Transformador beta/metabolismo , beta-Galactosidase/metabolismo
15.
Exp Dermatol ; 21(8): 592-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22643125

RESUMO

Mutations in Connexin26 (Cx26) give rise to a spectrum of dominantly inherited hyperproliferating skin disorders, the severest being keratitis-ichthyosis-deafness (KID) syndrome, an inflammatory skin disorder, with patients prone to opportunistic infections. We compared the effects of peptidoglycan (PGN) extracted from the skin commensal Staphylococcus epidermidis and the opportunistic pathogen Staphylococcus aureus on interleukin-6 and connexin expression in HaCaT cells (a keratinocyte cell line) and connexin channel activity in HaCaT and HeLa (connexin deficient) cells transfected to express KID and non-KID Cx26 mutations. In both cell types, PGN from S. aureus induced hemichannel activity in cells expressing KID mutants as monitored by ATP release assays following 15-min challenge, while that from S. epidermidis evoked a response in HeLa cells. In KID mutant expressing cells, ATP release was significantly higher than in cells transfected with wild-type Cx26. No ATP release was observed in non-KID mutant transfected cells or in the presence of carbenoxolone, a connexin channel blocker. PGN isolated from S. aureus but not S. epidermidis induced interleukin-6 and Cx26 expression in HaCaT cells following 6-h challenge. Challenge by PGN from S. aureus evoked a greater interleukin-6 response in cells expressing KID mutants than in cells expressing wtCx26 or non-KID mutants. This response returned to basal levels if acute KID hemichannel signalling was blocked prior to PGN challenge. Thus, KID mutants form channels that can be triggered by the pro-inflammatory mediator PGN from opportunistic pathogens but not skin commensals, providing further insight into the genotype-phenotype relationship of Cx26 disorders.


Assuntos
Conexinas/genética , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Mutação/genética , Peptidoglicano/farmacologia , Dermatopatias Genéticas/genética , Staphylococcus aureus/metabolismo , Staphylococcus epidermidis/metabolismo , Trifosfato de Adenosina/metabolismo , Carbenoxolona/farmacologia , Linhagem Celular , Conexina 26 , Conexinas/metabolismo , Surdez/genética , Epiderme/anormalidades , Genótipo , Células HeLa , Humanos , Ictiose/genética , Interleucina-6/metabolismo , Queratinócitos/patologia , Ceratite/genética , Peptidoglicano/metabolismo , Fenótipo , Transfecção
16.
PLoS One ; 7(5): e36544, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22574182

RESUMO

The sequencing of numerous insect genomes has revealed dynamic changes in the number and identity of cytochrome P450 genes in different insects. In the evolutionary sense, the rapid birth and death of many P450 genes is observed, with only a small number of P450 genes showing orthology between insects with sequenced genomes. It is likely that these conserved P450s function in conserved pathways. In this study, we demonstrate the P450 gene, Cyp301a1, present in all insect genomes sequenced to date, affects the formation of the adult cuticle in Drosophila melanogaster. A Cyp301a1 piggyBac insertion mutant and RNAi of Cyp301a1 both show a similar cuticle malformation phenotype, which can be reduced by 20-hydroxyecdysone, suggesting that Cyp301a1 is an important gene involved in the formation of the adult cuticle and may be involved in ecdysone regulation in this tissue.


Assuntos
Sequência Conservada , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimologia , Drosophila melanogaster/crescimento & desenvolvimento , Epiderme/enzimologia , Epiderme/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Sequência de Bases , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/deficiência , Sistema Enzimático do Citocromo P-450/genética , Proteínas de Drosophila/química , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/efeitos dos fármacos , Ecdisterona/farmacologia , Epiderme/anormalidades , Epiderme/efeitos dos fármacos , Evolução Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Genoma de Inseto/genética , Masculino , Mutagênese Insercional , Fenótipo , Interferência de RNA , Fatores de Tempo
18.
PLoS Biol ; 9(7): e1001115, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21814493

RESUMO

The evolutionary fate of an allele ordinarily depends on its contribution to host fitness. Occasionally, however, genetic elements arise that are able to gain a transmission advantage while simultaneously imposing a fitness cost on their hosts. We previously discovered one such element in C. elegans that gains a transmission advantage through a combination of paternal-effect killing and zygotic self-rescue. Here we demonstrate that this element is composed of a sperm-delivered toxin, peel-1, and an embryo-expressed antidote, zeel-1. peel-1 and zeel-1 are located adjacent to one another in the genome and co-occur in an insertion/deletion polymorphism. peel-1 encodes a novel four-pass transmembrane protein that is expressed in sperm and delivered to the embryo via specialized, sperm-specific vesicles. In the absence of zeel-1, sperm-delivered PEEL-1 causes lethal defects in muscle and epidermal tissue at the 2-fold stage of embryogenesis. zeel-1 is expressed transiently in the embryo and encodes a novel six-pass transmembrane domain fused to a domain with sequence similarity to zyg-11, a substrate-recognition subunit of an E3 ubiquitin ligase. zeel-1 appears to have arisen recently, during an expansion of the zyg-11 family, and the transmembrane domain of zeel-1 is required and partially sufficient for antidote activity. Although PEEL-1 and ZEEL-1 normally function in embryos, these proteins can act at other stages as well. When expressed ectopically in adults, PEEL-1 kills a variety of cell types, and ectopic expression of ZEEL-1 rescues these effects. Our results demonstrate that the tight physical linkage between two novel transmembrane proteins has facilitated their co-evolution into an element capable of promoting its own transmission to the detriment of organisms carrying it.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Proteínas de Membrana/genética , Espermatozoides/metabolismo , Toxinas Biológicas/genética , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/embriologia , Proteínas de Caenorhabditis elegans/metabolismo , Desenvolvimento Embrionário , Epiderme/anormalidades , Feminino , Dosagem de Genes , Genes Letais , Ligação Genética , Hereditariedade , Masculino , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Músculos/anormalidades , Organelas/metabolismo , Fenótipo , Filogenia , Estrutura Terciária de Proteína , Toxinas Biológicas/metabolismo
19.
Mol Biol Cell ; 22(18): 3331-43, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21795395

RESUMO

Teneurins are a family of phylogenetically conserved proteins implicated in pattern formation and morphogenesis. The sole orthologue in Caenorhabditis elegans, ten-1, is important for hypodermal cell migration, neuronal migration, path finding and fasciculation, gonad development, and basement membrane integrity of some tissues. However, the mechanisms of TEN-1 action remain to be elucidated. Using a genome-wide RNA interference approach, we identified phy-1 as a novel interaction partner of ten-1. phy-1 codes for the catalytic domain of collagen prolyl 4-hydroxylase. Loss of phy-1 significantly enhanced the embryonic lethality of ten-1 null mutants. Double-mutant embryos arrested during late elongation with epidermal defects, disruption of basement membranes, and detachment of body wall muscles. We found that deletion of phy-1 caused aggregation of collagen IV in body wall muscles in elongated embryos and triggered the loss of tissue integrity in ten-1 mutants. In addition, phy-1 and ten-1 each genetically interact with genes encoding collagen IV. These findings support a functional mechanism in which loss of ten-1, together with a reduction of assembled and secreted basement membrane collagen IV protein, leads to detachment of the epidermis from muscle cells during late elongation of the embryo when mechanical stress is generated by muscle contractions.


Assuntos
Membrana Basal/metabolismo , Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Colágeno Tipo IV/metabolismo , Epistasia Genética , Proteínas de Membrana/genética , Pró-Colágeno-Prolina Dioxigenase/genética , Animais , Membrana Basal/anormalidades , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Epiderme/anormalidades , Epiderme/metabolismo , Técnicas de Silenciamento de Genes , Genes Letais , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Proteínas de Membrana/metabolismo , Músculos/anormalidades , Músculos/metabolismo , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Interferência de RNA
20.
J Am Acad Dermatol ; 64(5): 974-80, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20619487

RESUMO

In the digital age, personal identification by fingerprints (epidermal ridges) has become more frequent and is often required for biometric passports. The more fingerprints are analyzed, the more variants in their formation are documented. Individuals completely missing fingerprints as an isolated finding are extremely rare. Only 4 kindreds have been described to date, with additional clinical features in most cases. We describe a female patient with missing epidermal ridges on the fingers, palms, toes, and soles as an isolated feature. Absent fingerprints, or adermatoglyphia, were inherited over 4 generations of her family in an autosomal dominant fashion. We present the clinical features of the index patient, and compare the case with previous reports in the literature. Because of problems in personal identification, this embryologic malformation caused the patient significant difficulties when traveling to other countries, which is why we name it the immigration delay disease.


Assuntos
Dermatoglifia , Epiderme/anormalidades , Adulto , Emigrantes e Imigrantes , Feminino , Medicina Legal , Humanos , Linhagem , Terminologia como Assunto
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