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1.
Neotrop Entomol ; 48(2): 332-339, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30374736

RESUMO

Diloboderus abderus (Sturm, 1826) (Coleoptera: Melolonthidae) is a serious soil pest of corn, wheat, oat, and natural and cultivated pastures in Argentina, Paraguay, Uruguay, and southern Brazil. Despite its economic importance, the genetic diversity and population structure of D. abderus remain unknown. We sequenced a fragment of the mitochondrial gene cytochrome oxidase I region (COI), of six populations of D. abderus from the Southern Cone of America. The mtDNA marker revealed a high haplotype diversity, high pairwise FST values, and significant genetic variations among populations. No correlation was found between genetic and geographical distances, yet the most common haplotype (Dab01) was present in four out of the six populations. Analysis of molecular variance showed that most of the variation was within populations of D. abderus. Tajima's D and Fu's FS tests indicated no evidence that D. abderus populations are under recent expansion. Our results indicate that genetic-based traits will likely remain localized or spread slowly, and management strategies need to be undertaken on a small scale.


Assuntos
Besouros/genética , Genética Populacional , Filogeografia , Animais , DNA Mitocondrial/genética , Marcadores Genéticos , Variação Genética , Haplótipos , Análise de Sequência de DNA , América do Sul
2.
Genet Mol Res ; 16(3)2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28829894

RESUMO

We provided the first scientific record of Melanagromyza sojae (Zehntner, 1900), through molecular characterization of partial mtDNA COI gene, that confirms the occurrence of this pest in Paraguay. Previously reported in Brazil, an outbreak of larvae of M. sojae known as the soybean stem fly (SSF) that belongs to the family Agromyzidae, was also noted in soybean fields from the Canindeyú, Alto Paraná and Itapúa Departments in Paraguay. This pest is highly polyphagous, attacking various host plant species from the family Fabaceae, such as soybean and other beans. The implications of SSF detection in Paraguay are discussed in relation to the current soybean cultivation practices from this agriculturally important South American region, including Brazil.


Assuntos
Dípteros/genética , Glycine max/parasitologia , Animais , DNA Mitocondrial/química , DNA Mitocondrial/genética , Dípteros/patogenicidade , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , Paraguai
3.
Genet Mol Res ; 15(2)2016 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-27420989

RESUMO

Soybean Stem Fly (SSF), Melanagromyza sojae (Zehntner), belongs to the family Agromyzidae and is highly polyphagous, attacking many plant species of the family Fabaceae, including soybean and other beans. SSF is regarded as one of the most important pests in soybean fields of Asia (e.g., China, India), North East Africa (e.g., Egypt), parts of Russia, and South East Asia. Despite reports of Agromyzidae flies infesting soybean fields in Rio Grande do Sul State (Brazil) in 1983 and 2009 and periodic interceptions of SSF since the 1940s by the USA quarantine authorities, SSF has not been officially reported to have successfully established in the North and South Americas. In South America, M. sojae was recently confirmed using morphology and its complete mitochondrial DNA (mtDNA) was characterized. In the present study, we surveyed the genetic diversity of M. sojae, collected directly from soybean host plants, using partial mtDNA cytochrome oxidase I (COI) gene, and provide evidence of multiple (>10) maternal lineages in SSF populations in South America, potentially representing multiple incursion events. However, a single incursion involving multiple-female founders could not be ruled out. We identified a haplotype that was common in the fields of two Brazilian states and the individuals collected from Australia in 2013. The implications of SSF incursions in southern Brazil are discussed in relation to the current soybean agricultural practices, highlighting an urgent need for better understanding of SSF population movements in the New World, which is necessary for developing effective management options for this significant soybean pest.


Assuntos
Dípteros/genética , Polimorfismo Genético , Distribuição Animal , Animais , Brasil , Dípteros/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Efeito Fundador , Haplótipos , Proteínas de Insetos/genética
4.
Genet Mol Res ; 15(2)2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27173209

RESUMO

Since its detection in Brazil in 2013, the Old World cotton bollworm Helicoverpa armigera has been reported in Argentina, Paraguay, and Bolivia. Here we present evidence extending the South American range of H. armigera to Uruguay, using polymerase chain reaction and sequencing of the partial mitochondrial DNA (mtDNA) cytochrome oxidase I region. Molecular characterization of this gene region from individuals from Paraguay also supports previous morphological identification of H. armigera in Paraguay. Shared mtDNA haplotypes in H. armigera from Brazil, Uruguay, and Paraguay were identified. Additional surveying of populations in this region will be imperative to better monitor and understand factors that are underpinning its presence and successful adaptation in these South American regions. We discuss our findings with respect to the development of resistance pest management strategies of this invasive insect pest in a predominantly monoculture soybean crop landscape in the Southern Cone region.


Assuntos
DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , Lepidópteros/genética , Adaptação Fisiológica/genética , Animais , Lepidópteros/patogenicidade , Lepidópteros/fisiologia , Paraguai , Uruguai
6.
Eur J Hum Genet ; 9(3): 197-203, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11313759

RESUMO

The adhesive proteins of the desmosome type of cell junction consist of two types of cadherin found exclusively in that structure, the desmogleins and desmocollins, coded by two closely linked loci on human chromosome 18q12.1. Recently we have identified a mutation in the DSG1 gene coding for desmoglein 1 as the cause of the autosomal dominant skin disease striate palmoplantar keratoderma (SPPK) in which affected individuals have marked hyperkeratotic bands on the palms and soles. In the present study we present the complete exon-intron structure of the DSG1 gene, which occupies approximately 43 kb, and intron primers sufficient to amplify all the exons. Using these we have analysed the mutational changes in this gene in five further cases of SPPK. All were heterozygotic mutations in the extracellular domain leading to a truncated protein, due either to an addition or deletion of a single base, or a base change resulting in a stop codon. Three mutations were in exon 9 and one in exon 11, both of which code for part of the third and fourth extracellular domains, and one was in exon 2 coding for part of the prosequence of this processed protein. This latter mutation thus results in the mutant allele synthesising only 25 amino acid residues of the prosequence of the protein so that this is effectively a null mutation implying that dominance in the case of this mutation was caused by haploinsufficiency. The most severe consequences of SPPK mutations are in regions of the body where pressure and abrasion are greatest and where desmosome function is most necessary. SPPK therefore provides a very sensitive measure of desmosomal function.


Assuntos
Caderinas/genética , Ceratodermia Palmar e Plantar/genética , Mutação , Sequência de Bases , Primers do DNA , Desmogleína 1 , Éxons , Humanos , Íntrons
7.
Scand J Immunol ; 52(6): 525-30, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11119255

RESUMO

The human interleukin(IL)-18 is a key regulator of interferon(IFN)-gamma production and T-cell differentiation. Here we report the complete genomic structure and characterization of the 5'untranslated promoter region of the human IL-18 gene. The gene is composed of six exons and five introns, spanning approximately 19. 5kb. Promoter activity of the 5'-flanking region was investigated with a luciferase reporter gene assay. Transient transfection studies demonstrate a constitutive expression of the IL-18 gene in monocytic U937 and THP-1 cells. For this constitutive expression at least 92 base pairs of the promoter region are essential as shown by consecutive 5' promoter deletions in both cell types. DNA protein binding experiments revealed specific binding of activated signal transducer and activator of transcription factor-5 (STAT5) but not of STAT3 to three consensus sequences upstream in the promoter region. Cotransfection of STAT5 resulted in increased induction of the IL-18 promoter in the U937 and THP-1 cells.


Assuntos
Interleucina-18/genética , Proteínas do Leite , Sequência de Bases , Sítios de Ligação , Proteínas de Ligação a DNA/metabolismo , Éxons , Genoma Humano , Biblioteca Genômica , Humanos , Íntrons , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Ligação Proteica , RNA Mensageiro/genética , Fator de Transcrição STAT5 , Transativadores/metabolismo , Fatores de Transcrição/metabolismo
8.
Prenat Diagn ; 20(10): 842-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11038467

RESUMO

We report on the incidental prenatal detection of an interstitial X-chromosomal deletion in a male fetus and his mother by fetal sexing with a primer pair recognizing an X-Y homologous locus (DXYS19), formerly unassigned on the X chromosome. The proband asked for prenatal diagnosis because of her elevated age and risk of Duchenne muscular dystrophy (DMD). Prior to molecular genetic testing for DMD, fetal sexing was carried out on DNA prepared from cultured amniocytes. PCR analysis revealed the expected Y-chromosomal product, but did not show the constitutive X-chromosomal fragment. The absence of the X-chromosomal fragment in the fetus and on one X chromosome of the mother was confirmed by Southern hybridization of HindIII restricted DNA with probe pJA1165 (DXYS19). DXYS19X was mapped to Xp22.3 by combining several approaches, including: (1) analysis of somatic cell hybrid lines containing different fragments of the human X chromosome; (2) Southern hybridization of a yeast artificial chromosome (YAC)-filter panel provided by the Resource Center/Primary Database (RZPD); (3) FISH analysis; and (4) re-evaluation of two patients with interstitial deletions in Xp22.3. The extent of the deletion in the fetus was estimated by further markers from Xp22.3 and found to include the STS gene. Mental retardation could not be excluded since some mentally retarded patients exhibit overlapping deletions.


Assuntos
Doenças Fetais/genética , Deleção de Genes , Deficiência Intelectual/genética , Diagnóstico Pré-Natal , Processos de Determinação Sexual , Cromossomo X/genética , Adulto , Amniocentese , Southern Blotting , Primers do DNA , Feminino , Doenças Fetais/diagnóstico , Ligação Genética , Humanos , Hibridização in Situ Fluorescente , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/embriologia , Masculino , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Gravidez
9.
Prenat Diagn ; 20(2): 152-5, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10694689

RESUMO

Wolf-Hirschhorn Syndrome (WHS) is caused by distal deletion of the short arm of chromosome 4 and is characterized by growth deficiency, mental retardation, a distinctive, 'greek-helmet' facial appearance, microcephaly, ear lobe anomalies, and sacral dimples. We report a family with a balanced chromosomal translocation 4;18(p15.32;p11.21) in the father and an unbalanced translocation resulting in partial monosomy 4 and partial trisomy 18 in one living boy and a prenatally diagnosed male fetus. Both showed abnormalities consistent with WHS and had in addition aplasia of one umbilical artery. Karyotyping of another stillborn fetus revealed a supernumerary derivative chromosome der(18)t(4;18)(p15.32;p11.21) of paternal origin and two normal chromosomes 4. The umbilical cord had three normal vessels. A third stillborn fetus with the same balanced translocation as the father had a single umbilical artery and hygroma colli.


Assuntos
Cromossomos Humanos Par 18 , Cromossomos Humanos Par 4 , Diagnóstico Pré-Natal , Translocação Genética , Anormalidades Múltiplas/genética , Feminino , Transtornos do Crescimento/genética , Humanos , Recém-Nascido , Deficiência Intelectual/genética , Cariotipagem , Masculino , Monossomia , Linhagem , Gravidez , Síndrome , Trissomia
10.
Med Klin (Munich) ; 95(12): 697-700, 2000 Dec 15.
Artigo em Alemão | MEDLINE | ID: mdl-11198558

RESUMO

BACKGROUND: Cystic fibrosis is the most common hereditary disorder among Caucasians. Most of the patients are diagnosed as children. However, some cases are going undiagnosed into adulthood and are then often misdiagnosed because the non-pediatricians do not know cystic fibrosis very well and do not consider this diagnosis in adult patients. CASE REPORT: We present the medical history of a woman, who was diagnosed with cystic fibrosis at the age of 39 years, although she had suffered from bronchiectasis, pancreatic insufficiency and liver cirrhosis since many years. Her medical history was long with some diagnosis, but because of her age nobody considered the final diagnosis. CONCLUSION: In adult patients with bronchiectasis, liver cirrhosis and pancreatic insufficiency in combination or with only one of these symptoms, cystic fibrosis should be included into the differential diagnosis.


Assuntos
Fibrose Cística/diagnóstico , Adulto , Bronquiectasia/diagnóstico , Diagnóstico Diferencial , Insuficiência Pancreática Exócrina/diagnóstico , Feminino , Humanos , Cirrose Hepática/diagnóstico , Equipe de Assistência ao Paciente , Tomografia Computadorizada por Raios X
11.
Exp Clin Endocrinol Diabetes ; 107(8): 568-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10612489

RESUMO

Cystic fibrosis (CF) is one of the most common recessively inherited disorders in Caucasian populations and is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. A three base deletion known as deltaF508 occurs on about 70%, of CF chromosomes and accounts for the high prevalence of the disease. Since type 2 diabetes mellitus occurs more frequently in relatives of patients with CF than in the normal population, we addressed the hypothesis whether heterozygosity for deltaF508 might be a genetic risk factor for type 2 diabetes. We screened 301 patients with type 2 diabetes mellitus which had been treated for at least three years from diagnosis by diet or oral antihyperglycemic agents. Healthy controls (n = 282) had no family history for diabetes. The genotype distribution did not differ significantly between patients with type 2 diabetes (2% heterozygotes) and controls (3% heterozygotes). According to these results, we conclude, that the deltaF508 mutation in its heterozygous form does not represent a major genetic risk factor for type 2 diabetes mellitus.


Assuntos
Fibrose Cística/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Mutação , Índice de Massa Corporal , Fibrose Cística/complicações , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
12.
Hum Mol Genet ; 8(6): 971-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10332028

RESUMO

The N-terminal extracellular domain of the cadherins, calcium-dependent cell adhesion molecules, has been shown by X-ray crystallography to be involved in two types of interaction: lateral strand dimers and adhesive dimers. Here we describe the first human mutation in a cadherin present in desmosome cell junctions that removes a portion of this highly conserved first extracellular domain. The mutation, in the DSG1 gene coding for a desmoglein (Dsg1), results in the deletion of the first and much of the second beta-strand of the first cadherin repeat and part of the first Ca2+-binding site, and would be expected to compromise strand dimer formation. It causes a dominantly inherited skin disease, striate palmoplantar keratoderma (SPPK), mapping to chromosome 18q12.1, in which affected individuals have marked hyperkeratotic bands on the palms and soles. In a three generation Dutch family with SPPK, we have found a G-->A transition in the 3" splice acceptor site of intron 2 of the DSG1 gene which segregated with the disease phenotype. This causes aberrant splicing of exon 2 to exon 4, which are in-frame, with the consequent removal of exon 3 encoding part of the prosequence, the mature protein cleavage site and part of the first extracellular domain. This mutation emphasizes the importance of this part of the molecule for cadherin function, and of the Dsg1 protein and hence desmosomes in epidermal function.


Assuntos
Caderinas/genética , Genes Dominantes , Ceratodermia Palmar e Plantar/genética , Pele/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Proteínas do Citoesqueleto/genética , DNA/química , DNA/genética , Análise Mutacional de DNA , Desmogleína 1 , Desmogleínas , Desmoplaquinas , Desmossomos/química , Éxons/genética , Saúde da Família , Feminino , Dermatoses do Pé/genética , Dermatoses do Pé/patologia , Ligação Genética , Humanos , Ceratodermia Palmar e Plantar/patologia , Masculino , Dados de Sequência Molecular , Linhagem , Mutação Puntual , Polimorfismo Conformacional de Fita Simples , Splicing de RNA/genética , RNA Mensageiro/genética , Deleção de Sequência , Pele/patologia
13.
J Pathol ; 189(4): 623-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10629567

RESUMO

Gonadoblastomas are seen almost exclusively in dysgenetic gonads of patients with a chromosomal mosaicism of 45,X and an additional Y-bearing cell line. This paper presents a case of a Turner mosaic patient with 45,X/46,X,+mar karyotype, who developed a unilateral microscopic gonadoblastoma. Cytogenetic and molecular analysis confirmed a Y-chromosomal origin of the marker chromosome, with a deletion of the distal Yq arm and the proposed region of a so far undefined gonadoblastoma locus (GBY) present. One of the candidate genes within the postulated GBY region is TSPY (testis-specific protein Y-encoded). To study the TSPY protein expression, an anti-fusion protein antibody was used for immunohistochemistry of the patient's gonads. In contrast to the dysgenetic gonad, an intense immunoreaction was found in gonadoblastoma tumour cells of the other gonad. These results confirm the high level of TSPY protein expression by these cells and demonstrate the value of this antibody as an additional marker to confirm the diagnosis of gonadoblastoma.


Assuntos
Proteínas de Ligação a DNA/análise , Gonadoblastoma/metabolismo , Proteínas Nucleares , Neoplasias Ovarianas/metabolismo , Fatores de Transcrição , Síndrome de Turner/metabolismo , Adolescente , Biomarcadores/análise , Proteínas de Ciclo Celular , Análise Citogenética , Feminino , Deleção de Genes , Gonadoblastoma/genética , Gonadoblastoma/patologia , Humanos , Imuno-Histoquímica , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Proteína da Região Y Determinante do Sexo , Síndrome de Turner/genética , Síndrome de Turner/patologia , Cromossomo Y
14.
Genomics ; 62(3): 445-55, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10644442

RESUMO

We describe the assembly of a cosmid and PAC contig of approximately 700 kb on human chromosome 18q12 spanning the DSC and DSG genes coding for the desmocollins and desmogleins. These are members of the cadherin superfamily of calcium-dependent cell adhesion proteins present in the desmosome type of cell junction found especially in epithelial cells. They provide the strong cell-cell adhesion generated by this type of cell junction for which expression of both a desmocollin and a desmoglein is required. In the autoimmune skin diseases pemphigus foliaceous and pemphigus vulgaris (PV), where the autoantigens are, respectively, encoded by the DSG1 and DSG3 genes, severe areas of acantholysis (cell separation), potentially life-threatening in the case of PV, are evident. Dominant mutations in the DSG1 gene causing striate palmoplantar keratoderma result in hyperkeratosis of the skin on the parts of the body where pressure and abrasion are greatest, viz., on the palms and soles. These genes are also candidate tumor suppressor genes in squamous cell carcinomas and other epithelial cancers. We have screened two chromosome 18-specific cosmid libraries by hybridization with previously isolated YAC clones and DSC and DSG cDNAs, and a whole genome PAC library, both by hybridization with the YACs and by screening by PCR using cDNA sequences and YAC end sequence. The contigs were extended by further PCR screens using STSs generated by vectorette walking from the ends of the cosmids and PACs, together with sequence from PAC ends. Despite screening of two libraries, the cosmid contig still had four gaps. The PAC contig filled these gaps and in fact covered the whole locus. The positions of 45 STSs covering the whole of this region are presented. The desmocollin and desmoglein genes, which are about 30-35 kb in size, are quite well separated at approximately 20-30 kb apart and are arranged in two clusters, one DSC cluster and one DSG cluster, which are transcribed outward from the interlocus region. The order of the genes is correlated with the spatial order of gene expression in the developing mouse embryo, and this, and previous transgenic experiments, suggests that long-range genetic elements that coordinate expression of these genes may be present. The complete bacterial clone contig described in this paper is thus a resource not only for future sequencing but also for investigations into the control of expression of these clustered genes.


Assuntos
Caderinas/genética , Cromossomos Humanos Par 18/genética , Mapeamento de Sequências Contíguas , Desmossomos/genética , Família Multigênica/genética , Bacteriófago P1/genética , Clonagem Molecular , Cosmídeos/genética , Marcadores Genéticos , Humanos , Sitios de Sequências Rotuladas
15.
Biochem J ; 329 ( Pt 1): 165-74, 1998 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9405290

RESUMO

The adhesive proteins in the desmosome type of cell junction consist of two members of the cadherin superfamily, the desmogleins and desmocollins. Both desmogleins and desmocollins occur as at least three different isoforms with various patterns of expression. The molecular mechanisms controlling the differential expression of the desmosomal cadherin isoforms are not yet known. We have begun an investigation of desmoglein gene expression by cloning and analysing the promoters of the human genes coding for the type 1 and type 3 desmogleins (DSG1 and DSG3). The type 1 isoform is restricted to the suprabasal layers of the epidermis and is the autoantigen in the autoimmune blistering skin disease pemphigus foliaceous. The type 3 desmoglein isoform is also expressed in the epidermis, but in lower layers than the type 1 isoform, and is the autoantigen in pemphigus vulgaris. Phage lambda genomic clones were obtained containing 4.2 kb upstream of the translation start site of DSG1 and 517 bp upstream of the DSG3 start site. Sequencing of 660 bp upstream of DSG1 and 517 bp upstream of DSG3 revealed that there was no obvious TATA box, but a possible CAAT box was present at -238 in DSG1 and at -193 in DSG3 relative to the translation start site. Primer extension analysis and RNase protection experiments revealed four putative transcription initiation sites for DSG1 at positions -163, -151, -148 and -141, and seven closely linked sites for DSG3, the longest being at -140 relative to the translation start site. The sequences at these possible sites at -166 to -159 in DSG1 (TTCAGTCC) and at -124 to -117 in DSG3 (CTTAGACT) have some similarity to the initiator sequence (CTCANTCT) described for a TATA-less promoter often from -3 to +5, and the true transcription initiator site might therefore be the A residue in these sequences. There were two regions of similarity between the DSG1 and DSG3 promoters just upstream of the transcription initiation sites, of 20 and 13 bp, separated by 41 bp in DSG1 and 36 bp in DSG3. The significance of these regions of similarity remains to be elucidated, but the results suggest that they represent a point at which these two desmoglein genes are co-ordinately regulated. Analysis of the upstream sequences revealed GC-rich regions and consensus binding sites for transcription factors including AP-1 and AP-2. Exon boundaries were conserved compared with the classical cadherin E-cadherin, but the equivalent of the second cadherin intron was lacking. A 4.2 kb region of the human DSG1 promoter sequence was linked to the lacZ gene reporter gene in such a way that there was only one translation start site, and this construct was used to generate transgenic mice. We present the first transgenic analysis of a promoter region taken from a desmosomal cadherin gene. Our results suggest that the 4.2 kb upstream region of DSG1 does not contain all the regulatory elements necessary for correct expression of this gene but might have elements that regulate activity during hair growth.


Assuntos
Caderinas/genética , Proteínas do Citoesqueleto/genética , Epiderme/metabolismo , Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Animais , Sequência de Bases , Caderinas/imunologia , Clonagem Molecular , Proteínas do Citoesqueleto/classificação , Desmocolinas , Desmogleína 1 , Desmogleína 3 , Desmogleínas , Desmoplaquinas , Células Epidérmicas , Genes Reporter , Histocitoquímica , Humanos , Óperon Lac , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Mapeamento por Restrição , Análise de Sequência de DNA , Transcrição Gênica , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
16.
Differentiation ; 62(2): 83-96, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9404003

RESUMO

Desmosomes contain two heterogeneous families of specialized cadherins (desmogleins or Dsgs and desmocollins or Dscs), subtypes of which are known to be expressed in tissue-specific and differentiation-dependent patterns in adult epithelial tissues. To examine the temporal and spatial order in which the individual desmosomal cadherins are expressed during stratified epithelial development we have obtained partial cDNA clones of all six murine desmosomal cadherins and have carried out in situ hybridization analysis on E12.5 to E16.5 mouse embryos. The results indicate that the type 2, type 3 and type 1 desmosomal cadherin messages are not obligatorily expressed as pairs during stratified epithelial morphogenesis. Instead the individual genes appear to be transcribed in hierarchical, overlapping temporal and spatial patterns extending from DSG2 to DSC1. DSG2 was the most uniformly expressed message in all E12.5 epithelia, gradually becoming confined to the basal cell layers during epithelial stratification indicating that its transcription was restricted to undifferentiated cells. In contrast, DSC2 message was expressed variably in early epithelia and was strongly upregulated in the suprabasal cell layers during the stratification of wet-surfaced epithelia. DSC3 message was expressed before that of DSG3 in the dental and lingual epithelium where its spatial distribution matched that of DSG2, but after DSG3 in the non-glandular gastric epithelium. DSC3 transcripts became confined to the lower layers of stratifying epithelia but were usually less basally restricted than those of DSG2. Like DSC2, DSG3 mRNA was strongly upregulated in the suprabasal layers of wet-surfaced epithelia as they stratified. Upregulation of DSG1 message was temporally linked to that of DSG3 in all tissues apart from the non-glandular gastric epithelium.


Assuntos
Proteínas do Citoesqueleto/genética , Regulação da Expressão Gênica no Desenvolvimento , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/química , DNA Complementar/isolamento & purificação , Desmocolinas , Desmogleína 1 , Desmogleína 2 , Desmogleína 3 , Desmogleínas , Desmoplaquinas , Epitélio/embriologia , Camundongos , Dados de Sequência Molecular , Morfogênese , Transcrição Gênica
18.
Genomics ; 42(2): 208-16, 1997 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9192840

RESUMO

The desmocollins and desmogleins are members of the cadherin family of adhesive proteins present in the desmosome type of cell-cell junction. All of the known desmoglein and desmocollin isoforms, which have differing tissue and developmental distributions, are coded by very closely linked genes at 18q12.1. We have previously described YAC clones carrying all three known desmoglein (DSG) genes. We have now isolated YAC clones that carry all three known desmocollin genes (DSC1, 2, and 3) from two libraries and also isolated clones that join the DSC locus to the DSG locus, forming a complete contig for the region. Absence of chimeric ends for some of the YACs was confirmed by isolating Vectorette PCR products for the YAC ends and mapping the derived DNA sequences back to other YACs from CEPH. The whole DSC/DSG gene complex occupies no more than about 700 kb, and the genes are arranged in the order cen-3'-DSC3-DSC2-DSC1-5'-5'-DSG1-DSG3-D SG2-3'-tel, so that the two gene clusters are transcribed outward from the interlocus region. A P1 clone carrying part of DSC2 and DSC3 confirmed the relative orientation of transcription of these two genes. The conservation of close genetic linkage may be of trivial importance related to the recent duplication of these genes or may be because there is a region within the locus that is involved in coordinating the expression of the desmoglein and desmocollin genes.


Assuntos
Cromossomos Humanos Par 18/genética , Proteínas do Citoesqueleto/genética , Glicoproteínas de Membrana/genética , Sequência de Bases , Caderinas/genética , Quimera , Mapeamento Cromossômico , Cromossomos Artificiais de Levedura/genética , Clonagem Molecular , DNA/genética , Primers do DNA/genética , Desmocolinas , Desmogleína 1 , Desmogleínas , Desmoplaquinas , Desmossomos/genética , Humanos , Dados de Sequência Molecular , Família Multigênica , Reação em Cadeia da Polimerase , Sitios de Sequências Rotuladas
19.
Hum Mol Genet ; 5(11): 1801-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8923009

RESUMO

TSPY, the 'testis-specific protein, Y-encoded', is the product of a tandem gene cluster on human proximal Yp. In order to gain insight into the function of this locus, we have analysed (I) the diversity of RNAs transcribed from the cluster, (II) the sequence homology of the deduced TSPY to other proteins, and (iii) its protein properties both in tissue extracts and in tissue sections, using a TSPY-specific antiserum. We have identified a set of distinct TSPY transcripts with diverse exon compositions. We show that TSPY has homology with other human and non-human proteins, including SET and NAP, factors that are suggested to play a role in DNA replication. Protein analysis revealed TSPY to occur mainly in a modified, putatively phosphorylated form. By immunostaining it was detected in distinct subsets of spermatogonia. TSPY was also strongly immunostained in early testicular carcinoma in situ (CIS), while seminomatous tumour cells stained less intensely. The spermatogonial cells of two XY-TFM-females gave a strong immune response. The data presented here point to a phosphorylation-dependent TSPY-function in early spermatogenesis, immediately prior to the spermatogonia-to-spermatocyte transition, and in early testicular tumorigenesis.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Proteínas Nucleares , Testículo/metabolismo , Fatores de Transcrição , Sequência de Aminoácidos , Síndrome de Resistência a Andrógenos , Carcinoma in Situ/metabolismo , Proteínas de Ciclo Celular , Proteínas Cromossômicas não Histona , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/química , Chaperonas de Histonas , Humanos , Tumor de Células de Leydig/metabolismo , Masculino , Dados de Sequência Molecular , Família Multigênica/genética , Proteína 1 de Modelagem do Nucleossomo , Fosforilação , Proteínas/genética , RNA Mensageiro/genética , Homologia de Sequência de Aminoácidos , Proteína da Região Y Determinante do Sexo , Espermatogônias/química , Neoplasias Testiculares/metabolismo , Testículo/química
20.
Proc Natl Acad Sci U S A ; 93(15): 7811-5, 1996 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-8755558

RESUMO

Patients with disorders involving imprinted genes such as Angelman syndrome (AS) and Prader-Willi syndrome (PWS) can have a mutation in the imprinting mechanism. Previously, we identified an imprinting center (IC) within chromosome 15q11-ql3 and proposed that IC mutations block resetting of the imprint, fixing on that chromosome the parental imprint (epigenotype) on which the mutation arose. We now describe four new microdeletions of the IC, the smallest (6 kb) of which currently defines the minimal region sufficient to confer an AS imprinting mutation. The AS deletions all overlap this minimal region, centromeric to the PWS microdeletions, which include the first exon of the SNRPN gene. None of five genes or transcripts in the 1.0 Mb vicinity of the IC (ZNF127, SNRPN, PAR-5, IPW, and PAR-1), each normally expressed only from the paternal allele, was expressed in cells from PWS imprinting mutation patients. In contrast, AS imprinting mutation patients show biparental expression of SNRPN and IPW but must lack expression of the putative AS gene 250-1000 kb distal of the IC. These data strongly support a model in which the paternal chromosome of these PWS patients carries an ancestral maternal epigenotype, and the maternal chromosome of these AS patients carries an ancestral paternal epigenotype. The IC therefore functions to reset the maternal and paternal imprints throughout a 2-Mb imprinted domain within human chromosome 15q11-q13 during gametogenesis.


Assuntos
Síndrome de Angelman/genética , Cromossomos Humanos Par 15 , Impressão Genômica , Polimorfismo Genético , Síndrome de Prader-Willi/genética , Deleção de Sequência , Sequência de Bases , Mapeamento Cromossômico , Primers do DNA , Família , Feminino , Marcadores Genéticos , Homozigoto , Humanos , Masculino , Metilação , Dados de Sequência Molecular , Mães , Linhagem , Reação em Cadeia da Polimerase , Transcrição Gênica
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