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1.
Zootaxa ; 3957(1): 49-58, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-26249052

RESUMO

Mutilla frigidula Cresson, 1902 was transferred to Tobantilla by Williams et al. (2011), based on morphological similarities with females of that genus. Discovery of the male of this species indicated significant morphological differences from Tobantilla. We therefore erect the genus, Frigitilla gen. nov., for Mutilla frigidula. Herein, we describe the male of F. frigidula (Cresson, 1902), comb. nov., associate it with its host (Trypoxylon spp.), and discuss its relations to other mutillid genera. The impact of collecting method and specimen age on the integumental coloration of specimens is discussed, emphasizing the need to diagnose species on consistent structural features rather than differences in color pattern.


Assuntos
Vespas/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Feminino , Masculino , Tamanho do Órgão , Vespas/anatomia & histologia , Vespas/crescimento & desenvolvimento
2.
Mater Sci Eng C Mater Biol Appl ; 33(4): 2213-20, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23498250

RESUMO

A innovative 5-Cl-8-oxyquinolinepropoxycalix[4]arene ligand (2) have been prepared, exhibiting, at room temperature, blue fluorescent light emission and resulting in shift band to green fluorescent light (fluorescence mode) in the presence of coordinated Eu(III) and Tb(III) ions. Terbium complex presented phosphorescence emission as noted by typical bands at 490 nm, 545 nm and 585 nm. TG/DTG data exhibited typical thermal behavior for these compounds, however DSC curves showed the melting temperature near 300 °C for the samples, demonstrating an unusual thermal stability when quinoline derivatives are attached to calix[4]arene matrix. This fact strongly suggests an effective approach to preparing the photoluminescent compound associating high chemical and thermal stability.


Assuntos
Calixarenos/química , Cloroquinolinóis/química , Luminescência , Temperatura , Acetonitrilas/química , Varredura Diferencial de Calorimetria , Európio/química , Ligantes , Espectroscopia de Ressonância Magnética , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Térbio/química , Termogravimetria
3.
Cytogenet Genome Res ; 125(1): 54-66, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19617697

RESUMO

Of the superfamily Muroidea (31 genera, 1578 species), the Sigmodontinae (74 genera, 377 species) is the second largest subfamily in number of species and represents a significant radiation of rodent biodiversity. Only 2 of the 74 genera are found in both North and South America (Sigmodon and Oryzomys) and the remainder are exclusively from South America. In recent molecular studies, the genus Sigmodon (Cricetidae, Sigmodontinae) has been considered sister to many other South American Sigmodontines [Steppan et al., 2004]. We examine the chromosomal evolution of 9 species of Sigmodon utilizing chromosomal paints isolated from S. hispidus, proposed to be similar to the ancestral karyotype [Elder, 1980]. Utilizing a phylogenetic hypothesis of a molecular phylogeny of Sigmodon [Henson and Bradley, 2009], we mapped shared chromosomal rearrangements of taxa on a molecular tree to estimate the evolutionary position of each rearrangement. For several species (S. hirsutus, S. leucotis, S. ochrognathus, S. peruanus, and S. toltecus), the karyotype accumulated few or no changes, but in three species (S. arizonae, S. fulviventer, and S. mascotensis) numerous karyotype rearrangements were observed. These rearrangements involved heterochromatic additions, centric fusions, tandem fusions, pericentric inversions, as well as the addition of interstitial DNA not identified by chromosome paints or C-banding. The hypothesis that the ancestral karyotype for this complex had a diploid number of 52, a fundamental number of 52, and a G-band pattern of which most, if not all are similar to that present in modern day S. hispidus fails to be rejected. This hypothesis remains viable as an explanation of chromosomal evolution in Sigmodontine rodents.


Assuntos
Evolução Biológica , Cromossomos/genética , Sigmodontinae/genética , Animais , Células Cultivadas , Bandeamento Cromossômico , Coloração Cromossômica , Feminino , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Modelos Genéticos , Filogenia , Sigmodontinae/classificação , Especificidade da Espécie
4.
Acta amaz ; 38(4): 789-797, dez. 2008. graf, tab
Artigo em Português | LILACS | ID: lil-504714

RESUMO

O Parque Nacional da Serra do Divisor (PNSD), localizado a noroeste do Estado do Acre, é considerado uma das áreas de maior diversidade da Amazônia. A importância de se considerar insetos em programas de conservação tem sido muito enfatizada. Vespas solitárias e sociais são componentes muito importantes dos ecossistemas, devido à posição que ocupam nas redes alimentares. Esse trabalho teve como objetivo realizar uma avaliação ecológica rápida da fauna de vespas do PNSD, para subsidiar a elaboração de um plano de manejo do referido parque. A amostragem foi realizada em 12 sítios de coleta, situados no interior de oito tipologias de vegetação. Os insetos foram coletados através de armadilhas Malaise, as quais foram expostas em todos os sítios por 24 horas, totalizando 288 horas de amostragem. Foram consideradas nas análises vespas das famílias Chalcididae, Eucharitidae, Evaniidae, Mutillidae, Pompilidae, Crabronidae e Vespidae. Ao todo, foram coletados 366 indivíduos distribuídos em 40 gêneros e 85 espécies. Os gêneros Ephuta (Mutillidae), Trypoxylon (Crabronidae) e Conura (Chalcididae) foram os mais ricos em espécies. Os sítios localizados na região norte do PNSD, considerada zona intangível e zona primitiva, foram os mais ricos em espécies. Cerca de 65 por cento das espécies foram exclusivas a um único sítio, o que significa que as amostras possuem pequena similaridade faunística. Algumas espécies coletadas são consideradas raras.


The Serra do Divisor National Park (PNSD), located at the northwest of Acre State, Amazonia, is considered an area of great biodiversity. The question of considering insects in conservation programs. Solitary and social wasps are important components of the terrestrial ecosystems due to their position in trophic webs. The present study aimed at making a rapid ecological assessment of the wasps from the PNSD in order to support the elaboration of a conservation and management plan for that park. The insects were sampled in 12 sites located in eight forest types by Malaise traps that operated in each for 24 hours, totaling 288 hours of sampling. The results on the families Chalcididae, Eucharitidae, Evaniidae, Mutillidae, Pompilidae, Crabronidae and Vespidae are presented here. On the whole, 366 wasps were collected representing 40 genera and 85 species. The genera Ephuta (Mutillidae), Trypoxylon (Crabronidae) and Conura (Chalcididae) were the most specious. The sites situated at the northern region of the PNSD, the intangible and primitive zones, were the most species rich. Some collected species were considered rare and about 65 percent of species were exclusive to only one site. This means that the samples have little faunal similarity.


Assuntos
Vespas , Himenópteros
5.
Chromosome Res ; 15(8): 1075-91, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18058249

RESUMO

Tenrecs (Tenrecidae) are a widely diversified assemblage of small eutherian mammals that occur in Madagascar and Western and Central Africa. With the exception of a few early karyotypic descriptions based on conventional staining, nothing is known about the chromosomal evolution of this family. We present a detailed analysis of G-banded and molecularly defined chromosomes based on fluorescence in situ hybridization (FISH) that allows a comprehensive comparison between the karyotypes of 11 species of two closely related Malagasy genera, Microgale (10 species) and Oryzorictes (one species), of the subfamily Oryzorictinae. The karyotypes of Microgale taiva and M. parvula (2n = 32) were found to be identical to that of O. hova (2n = 32) most likely reflecting the ancestral karyotypes of both genera, as well as that of the Oryzorictinae. Parsimony analysis of chromosomal rearrangements that could have arisen following Whole Arm Reciprocal Translocations (WARTs) showed, however, that these are more likely to be the result of Robertsonian translocations. A single most parsimonious tree was obtained that provides strong support for three species associations within Microgale, all of which are consistent with previous molecular and morphological investigations. By expanding on a recently published molecular clock for the Tenrecidae we were able to place our findings in a temporal framework that shows strong chromosomal rate heterogeneity within the Oryzorictinae. We use these data to critically examine the possible role of chromosomal rearrangements in speciation within Microgale.


Assuntos
Cromossomos de Mamíferos/genética , Eulipotyphla/classificação , Eulipotyphla/genética , Animais , Bandeamento Cromossômico , Coloração Cromossômica , Hibridização in Situ Fluorescente , Cariotipagem , Madagáscar , Translocação Genética
6.
Dis Esophagus ; 20(3): 256-64, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17509124

RESUMO

Barrett's esophagus, a metaplasia predisposed to malignant transformation, has been studied in vitro using esophageal adenocarcinoma cell lines. However, findings in such transformed cells may not be applicable to the non-neoplastic cells of benign Barrett's esophagus. Therefore, we have developed and characterized a Barrett's cell line derived from a patient without malignancy or dysplasia. Human Barrett's epithelial cells were immortalized with the insertion of hTERT (human telomerase reverse transcriptase) using a Cre-lox recombination system. We then examined properties of this continuous cell line, such as in vitro tumorigenicity, growth patterns, histological differentiation characteristics, karyotype, and checkpoint arrest mechanisms (e.g., p16, p21, and p53). Non-neoplastic Barrett's epithelial cells infected with hTERT (BAR-T cells) have been sustained in culture beyond 200 population doublings. BAR-T cells maintain a diploid chromosome number and exhibit non-neoplastic properties, such as contact inhibition and anchorage-dependent growth. BAR-T cells express differentiation Barrett's epithelial markers, such as villin and cytokeratins 4, 8 and 18, and stain positive for Alcian blue, indicating the presence of mucin-producing cells. Expression of checkpoint arrest proteins p21 and p53 are intact, while p16 expression is lost. Thus, we have created a human Barrett's cell line that is not malignantly transformed, and yet can be maintained indefinitely in culture. BAR-T cells are diploid, have histological differentiation markers characteristic of benign Barrett's epithelium, and also maintain appropriate expression of p21 and p53. This cell line should be a useful model for the study of the early events in carcinogenesis in Barrett's esophagus.


Assuntos
Esôfago de Barrett , Linhagem Celular/fisiologia , Telomerase , Transdução Genética , Esôfago de Barrett/metabolismo , Esôfago de Barrett/patologia , Técnicas de Cultura de Células , Linhagem Celular/patologia , Sobrevivência Celular , Inibição de Contato , Humanos , Proteínas de Neoplasias/metabolismo , Telômero/fisiologia
7.
Proc Biol Sci ; 274(1615): 1333-40, 2007 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-17374594

RESUMO

Despite marked improvements in the interpretation of systematic relationships within Eutheria, particular nodes, including Paenungulata (Hyracoidea, Sirenia and Proboscidea), remain ambiguous. The combination of a rapid radiation, a deep divergence and an extensive morphological diversification has resulted in a limited phylogenetic signal confounding resolution within this clade both at the morphological and nucleotide levels. Cross-species chromosome painting was used to delineate regions of homology between Loxodonta africana (2n=56), Procavia capensis (2n=54), Trichechus manatus latirostris (2n=48) and an outgroup taxon, the aardvark (Orycteropus afer, 2n=20). Changes specific to each lineage were identified and although the presence of a minimum of 11 synapomorphies confirmed the monophyly of Paenungulata, no change characterizing intrapaenungulate relationships was evident. The reconstruction of an ancestral paenungulate karyotype and the estimation of rates of chromosomal evolution indicate a reduced rate of genomic repatterning following the paenungulate radiation. In comparison to data available for other mammalian taxa, the paenungulate rate of chromosomal evolution is slow to moderate. As a consequence, the absence of a chromosomal character uniting two paenungulates (at the level of resolution characterized in this study) may be due to a reduced rate of chromosomal change relative to the length of time separating successive divergence events.


Assuntos
Coloração Cromossômica , Elefantes/genética , Procaviídeos/genética , Trichechus manatus/genética , Animais , Elefantes/classificação , Evolução Molecular , Procaviídeos/classificação , Masculino , Filogenia , Trichechus manatus/classificação
8.
Neotrop. entomol ; 35(3): 285-298, May-June 2006. ilus
Artigo em Inglês | LILACS | ID: lil-455789

RESUMO

Guilds of Aculeate solitary wasps and bees that nest in preexisting cavities in wood are important components of terrestrial ecosystems because they engage in several ecological interactions (e.g. predation and pollination) with other species of plants and animals. Spatial and temporal variations in richness and abundance of solitary wasps and bees can be related to changes in environmental structure and in the diversity of other groups of organisms. The nesting period of these Aculeata is their most critical life cycle stage. Females of solitary wasp and bee species invest relatively more time constructing and provisioning their nests than do females of social species. Differently from species that nest in the soil or construct exposed nests, the main factors affecting the reproductive success of solitary species nesting in preexisting wood holes are still unknown. Our objective is to provide an overview of the role of proximate causes of nesting failure or success among solitary wasps and bees (Aculeata), for designing effective conservation and management strategies for these Hymenoptera.


Espécies de vespas e abelhas solitárias que nidificam em cavidades pré-existentes no lenho de plantas integram uma guilda de nidificação e são importantes componentes da maioria dos ecossistemas terrestres. Isso se deve, em parte, ao grande número de interações (e.g. predação e polinização) que mantêm com outras espécies de organismos. Variações espaciais e temporais em sua abundância e riqueza podem estar correlacionadas a alterações na estrutura do ambiente. Uma fase crítica no ciclo de vida de vespas e abelhas solitárias é o período de nidificação. As fêmeas dessas espécies investem a maior parte de seu tempo de vida em construir e aprovisionar seus ninhos. Ao contrário do que ocorre para espécies que nidificam no solo ou fazem seus ninhos expostos, até o momento não houve tentativa alguma de discutir o conjunto de fatores que influenciam o sucesso de nidificação das espécies que nidificam em cavidades pré-existentes no lenho de plantas. Este artigo revê aspectos que afetam a nidificação desses Aculeata, com ênfase em fatores proximais, tais como a disponibilidade e características de cavidades no lenho. Compreender como esses fatores agem sobre a sobrevivência e o sucesso reprodutivo é de grande importância para a conservação e manejo dessas espécies.


Assuntos
Himenópteros/classificação , Himenópteros/crescimento & desenvolvimento , Himenópteros/embriologia , Abelhas , Vespas
9.
Neotrop Entomol ; 35(3): 285-98, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-18575687

RESUMO

Guilds of Aculeate solitary wasps and bees that nest in preexisting cavities in wood are important components of terrestrial ecosystems because they engage in several ecological interactions (e.g. predation and pollination) with other species of plants and animals. Spatial and temporal variations in richness and abundance of solitary wasps and bees can be related to changes in environmental structure and in the diversity of other groups of organisms. The nesting period of these Aculeata is their most critical life cycle stage. Females of solitary wasp and bee species invest relatively more time constructing and provisioning their nests than do females of social species. Differently from species that nest in the soil or construct exposed nests, the main factors affecting the reproductive success of solitary species nesting in preexisting wood holes are still unknown. Our objective is to provide an overview of the role of proximate causes of nesting failure or success among solitary wasps and bees (Aculeata), for designing effective conservation and management strategies for these Hymenoptera.


Assuntos
Abelhas , Comportamento de Nidação , Vespas , Madeira , Animais
10.
J Clin Endocrinol Metab ; 86(12): 5674-80, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11739418

RESUMO

Leri-Weill dyschondrosteosis (LWD) (MIM 127300) is a dominantly inherited skeletal dysplasia characterized phenotypically by Madelung wrist deformity, mesomelia, and short stature. LWD can now be defined genetically by haploinsufficiency of the SHOX (short stature homeobox-containing) gene. We have studied 21 LWD families (43 affected LWD subjects, including 32 females and 11 males, ages 3-56 yr) with confirmed SHOX abnormalities. We investigated the relationship between SHOX mutations, height deficit, and Madelung deformity to determine the contribution of SHOX haploinsufficiency to the LWD and Turner syndrome (TS) phenotypes. Also, we examined the effects of age, gender, and female puberty (estrogen) on the LWD phenotype. SHOX deletions were present in affected individuals from 17 families (81%), and point mutations were detected in 4 families (19%). In the LWD subjects, height deficits ranged from -4.6 to +0.6 SD (mean +/- SD = -2.2 +/- 1.0). There were no statistically significant effects of age, gender, pubertal status, or parental origin of SHOX mutations on height z-score. The height deficit in LWD is approximately two thirds that of TS. Madelung deformity was present in 74% of LWD children and adults and was more frequent and severe in females than males. The prevalence of the Madelung deformity was higher in the LWD vs. a TS population. The prevalence of increased carrying angle, high arched palate, and scoliosis was similar in the two populations. In conclusion, SHOX deletions or mutations accounted for all of our LWD cases. SHOX haploinsufficiency accounts for most, but not all, of the TS height deficit. The LWD phenotype shows some gender- and age-related differences.


Assuntos
Proteínas de Homeodomínio/genética , Osteocondrodisplasias/genética , Adolescente , Adulto , Estatura , Criança , Pré-Escolar , Feminino , Deleção de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Osteocondrodisplasias/complicações , Osteocondrodisplasias/patologia , Palato/anormalidades , Fenótipo , Mutação Puntual/genética , Escoliose/etiologia , Proteína de Homoeobox de Baixa Estatura , Síndrome de Turner/complicações , Síndrome de Turner/genética , Síndrome de Turner/patologia , Punho/anormalidades
11.
Am J Med Genet ; 102(4): 353-8, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11503163

RESUMO

We report on a man with neurofibromatosis type 1 (NF1) and Leri-Weill dyschondrosteosis (LWD). His father had NF1. His mother had LWD plus additional findings of Turner syndrome (TS): high arched palate, bicuspid aortic valve, aortic stenosis, and premature ovarian failure. The proband's karyotype was 46,X,dic(X;Y)(p22.3;p11.32). Despite having almost the same genetic constitution as 47,XXY Klinefelter syndrome, he was normally virilized, although slight elevation of serum gonadotropins indicated gonadal dysfunction. His mother's karyotype was mosaic 45,X[17 cells]/46,X,dic(X;Y)(p22.3;p11.32)[3 cells].ish dic(X;Y)(DXZ1 +,DYZ1 + ). The dic(X;Y) chromosome was also positive for Y markers PABY, SRY, and DYZ5, but negative for SHOX. The dic(X;Y) chromosome was also positive for X markers DXZ1 and a sequence < 300 kb from PABX, suggesting that the deletion encompassed only pseudoautosomal sequences. Replication studies indicated that the normal X and the dic(X;Y) were randomly inactivated in the proband's lymphocytes. LWD in the proband and his mother was explained by SHOX haploinsufficiency. The mother's female phenotype was most likely due to 45,X mosaicism. This family segregating Mendelian and chromosomal disorders illustrates extreme sex chromosome variation compatible with normal male and female sexual differentiation. The case also highlights the importance of karyotyping for differentiating LWD and TS, especially in patients with findings such as premature ovarian failure or aortic abnormalities not associated with isolated SHOX haploinsufficiency.


Assuntos
Proteínas de Ligação a DNA/genética , Neurofibromatose 1/genética , Proteínas Nucleares , Osteocondrodisplasias/genética , Fatores de Transcrição , Adulto , Bandeamento Cromossômico , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Neurofibromatose 1/diagnóstico , Osteocondrodisplasias/diagnóstico , Linhagem , Processos de Determinação Sexual , Proteína da Região Y Determinante do Sexo
12.
Cytogenet Cell Genet ; 93(3-4): 253-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11528121

RESUMO

G- and C-banding delimits two cytogenetic groups within the vlei rat, Otomys irroratus. One has a diploid number of 2n = 24, resulting from a centric fusion of chromosomes 7 and 12 of the O. irroratus standard coupled with a tandem fusion to chromosome 8. The second has a diploid number of 2n = 28, lacks the compound chromosome, and appears to have a far wider geographic distribution within South Africa. Additionally, the two groups differ through the presence of cytotype-specific heterozygous centric fusions and one to three B chromosomes which appear as floating polymorphisms in the 2n = 28 complex.


Assuntos
Cromossomos/genética , Evolução Molecular , Muridae/genética , Recombinação Genética/genética , Animais , Bandeamento Cromossômico , Fibroblastos , Cariotipagem , Polimorfismo Genético/genética , Ratos , África do Sul
13.
Hum Mol Genet ; 9(13): 1937-42, 2000 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-10942421

RESUMO

Bent tail (BN:) is a spontaneous, semi-dominant mutation on the mouse X chromosome that produces tail deformities and, rarely, open neural tube defects. Analysis of 292 normal male and affected male and female progeny from an intraspecific back-cross involving BN: supports a gene order of cen-DXMit89-18.5 +/- 2.3 cM-DXMit166-1.4 +/- 0.7 cM-BN:-1.0 +/- 0.6 cM-DXMit140 -4.8 +/- 1.3 cM-DXBay6-tel. A high frequency of sex chromosomal non-disjunction, unrelated to the BN: mutation, was also identified in the background strain. Refined genetic and physical mapping of the BN: critical region demonstrate that the mutation is associated with a <170 kb submicroscopic deletion that includes the anonymous microsatellite marker DXMit208 as well as the entire Zic3 locus. Human mutations in ZIC3 are associated with left-right axis malformations (MIM 306955, 208530, 207100). Abnormalities of abdominal and thoracic situs were also detected in viable BN: males and females. The presence of anal and spinal abnormalities in some of the human patients and the deletion of Zic3 in BN: mice support a key role for this gene in neural tube development and closure.


Assuntos
Deleção de Genes , Defeitos do Tubo Neural/genética , Cauda/anormalidades , Fatores de Transcrição/genética , Cromossomo X/genética , Animais , Southern Blotting , Cruzamentos Genéticos , Feminino , Proteínas de Homeodomínio , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Fenótipo , Mapeamento Físico do Cromossomo , Reação em Cadeia da Polimerase , Aberrações dos Cromossomos Sexuais , Vísceras/anormalidades
14.
Nat Genet ; 24(1): 79-83, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10615133

RESUMO

Leber congenital amaurosis (LCA, MIM 204000) accounts for at least 5% of all inherited retinal disease and is the most severe inherited retinopathy with the earliest age of onset. Individuals affected with LCA are diagnosed at birth or in the first few months of life with severely impaired vision or blindness, nystagmus and an abnormal or flat electroretinogram (ERG). Mutations in GUCY2D (ref. 3), RPE65 (ref. 4) and CRX (ref. 5) are known to cause LCA, but one study identified disease-causing GUCY2D mutations in only 8 of 15 families whose LCA locus maps to 17p13.1 (ref. 3), suggesting another LCA locus might be located on 17p13.1. Confirming this prediction, the LCA in one Pakistani family mapped to 17p13.1, between D17S849 and D17S960-a region that excludes GUCY2D. The LCA in this family has been designated LCA4 (ref. 6). We describe here a new photoreceptor/pineal-expressed gene, AIPL1 (encoding aryl-hydrocarbon interacting protein-like 1), that maps within the LCA4 candidate region and whose protein contains three tetratricopeptide (TPR) motifs, consistent with nuclear transport or chaperone activity. A homozygous nonsense mutation at codon 278 is present in all affected members of the original LCA4 family. AIPL1 mutations may cause approximately 20% of recessive LCA, as disease-causing mutations were identified in 3 of 14 LCA families not tested previously for linkage.


Assuntos
Proteínas de Transporte/genética , Cromossomos Humanos Par 17 , Mutação , Atrofias Ópticas Hereditárias/genética , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Sequência de Bases , Proteínas de Transporte/química , DNA Complementar , Proteínas do Olho , Feminino , Ligação Genética , Homozigoto , Humanos , Hibridização in Situ Fluorescente , Masculino , Dados de Sequência Molecular , Linhagem , Células Fotorreceptoras de Vertebrados/metabolismo , Glândula Pineal/metabolismo , Homologia de Sequência de Aminoácidos
15.
Genomics ; 61(2): 113-24, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10534397

RESUMO

Mice homozygous for the transgenic insertion in line OVE250 exhibit severe progressive glomerulonephritis. Ultrastructural changes in the glomerular basement membrane (GBM) at 2 weeks of age resemble those in Alport syndrome. The transgenic insertion site was mapped by FISH to mouse chromosome 1 close to Pax3. Genetic and molecular analyses identified a deletion of genomic DNA at the transgene insertion site. Exons 1 through 12 of the collagen IV gene Col4a4, exons 1 and 2 of the adjacent Col4a3 gene, and the intergenic promoter region are deleted. Transcripts of Col4a3 and Col4a4 are undetectable in mutant kidney, and both proteins are missing from the GBM. Persistent cellular proliferation in mutant kidneys suggests that interaction with the extracellular matrix may be important for cell maturation. Evolutionarily conserved sequence elements in the promoter regions of human and mouse Col4a3 and Col4a4 include a 19-bp element that was tandemly duplicated in the human lineage and a CTC box element common to several genes encoding extracellular matrix proteins. This new animal model of Alport syndrome, Col4Delta3-4, lacks both alpha3 and alpha4 chains of collagen IV and exhibits an earlier disease onset than mice lacking alpha3 only.


Assuntos
Colágeno/genética , Nefrite Hereditária/genética , Animais , Sequência de Bases , Membrana Basal/metabolismo , Membrana Basal/patologia , Bandeamento Cromossômico , Mapeamento Cromossômico , Colágeno/metabolismo , Modelos Animais de Doenças , Humanos , Rim/patologia , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Mutagênese Insercional , Nefrite Hereditária/metabolismo , Nefrite Hereditária/patologia , Regiões Promotoras Genéticas , Deleção de Sequência
16.
Biochem J ; 340 ( Pt 2): 425-32, 1999 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10333485

RESUMO

Carnitine palmitoyltransferase (CPT)-I catalyses the transfer of long-chain fatty acids from CoA to carnitine for translocation across the mitochondrial inner membrane. Expression of the 'liver' isoform of the CPT-I gene (CPT-Ialpha) is subject to developmental, hormonal and tissue-specific regulation. To understand the basis for control of CPT-Ialpha gene expression, we have characterized the proximal promoter of the CPT-Ialpha gene. Here, we report the sequence of 6839 base pairs of the promoter and the localization of the rat CPT-Ialpha gene to region q43 on chromosome 1. Our studies show that the first 200 base pairs of the promoter are sufficient to drive transcription of the CPT-Ialpha gene. Within this region are two sites that bind both Sp1 and Sp3 transcription factors. In addition, nuclear factor Y (NF-Y) binds the proximal promoter. Mutation at the Sp1 or NF-Y sites severely decreases transcription from the CPT-Ialpha promoter. Other protein binding sites were identified within the first 200 base pairs of the promoter by DNase I footprinting, and these elements contribute to CPT-Ialpha gene expression. Our studies demonstrate that CPT-Ialpha is a TATA-less gene which utilizes NF-Y and Sp proteins to drive basal expression.


Assuntos
Carnitina O-Palmitoiltransferase/genética , Mapeamento Cromossômico , Proteínas de Ligação a DNA/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Fígado/enzimologia , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/fisiologia , Animais , Sequência de Bases , Proteínas Estimuladoras de Ligação a CCAAT , DNA , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Ratos , Células Tumorais Cultivadas
17.
Mamm Genome ; 9(11): 863-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9799834

RESUMO

Mice with mutations at the downless (dl) locus have defects in hair follicle, tooth, sweat gland, preputial gland, Meibomian gland, and tail development. The dl phenotype is analogous to the human genetic disorder termed autosomal hypohidrotic (or anhidrotic) ectodermal dysplasia (HED). On the basis of the identification of two related transgenic insertional mutations in the downless gene, yeast artificial chromosomes (YACs) were identified that map to the critical region of mouse Chromosome (Chr) 10. To determine which of the YACs contain the dl gene, we generated YAC transgenic mice by mouse embryo microinjections. The 200-kb YAC B25.D9 was found to rescue all of the downless defects. In addition, the transgenic YAC rescued the dominant Sleek (Dlslk) allele. Since the sequences within the YAC are entirely deleted in one of the transgenic mutants, our results establish that Sleek encodes a dominant-negative protein whose effects can be reversed by expression of extra copies of the wild-type locus.


Assuntos
Cromossomos Artificiais de Levedura/metabolismo , Displasia Ectodérmica/genética , Mutagênese Insercional , Alelos , Animais , Modelos Animais de Doenças , Humanos , Hibridização in Situ Fluorescente , Camundongos , Camundongos Transgênicos , Linhagem , Fenótipo
18.
Nat Genet ; 20(2): 149-56, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9771707

RESUMO

Visceral left-right asymmetry occurs in all vertebrates, but the inversion of embryo turning (inv) mouse, which resulted following a random transgene insertion, is the only model in which these asymmetries are consistently reversed. We report positional cloning of the gene underlying this recessive phenotype. Although transgene insertion was accompanied by neighbouring deletion and duplication events, our YAC phenotype rescue studies indicate that the mutant phenotype results from the deletion. After extensively characterizing the 47-kb deleted region and flanking sequences from the wild-type mouse genome, we found evidence for only one gene sequence in the deleted region. We determined the full-length 5.5-kb cDNA sequence and identified 16 exons, of which exons 3-11 were eliminated by the deletion, causing a frameshift. The novel gene specifies a 1062-aa product with tandem ankyrin-like repeat sequences. Characterization of complementing and non-complementing YAC transgenic families revealed that correction of the inv mutant phenotype was concordant with integration and intact expression of this novel gene, which we have named inversin (Invs).


Assuntos
Proteínas/genética , Fatores de Transcrição , Sequência de Aminoácidos , Animais , Sequência de Bases , Cromossomos Artificiais de Levedura , Hibridização in Situ Fluorescente , Camundongos , Camundongos Mutantes , Camundongos Transgênicos , Dados de Sequência Molecular , Fenótipo , Deleção de Sequência
19.
Cytogenet Cell Genet ; 80(1-4): 179-84, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9678354

RESUMO

Chromosomal homologies among the X chromosomes of species representative of eight bovid subfamilies and most of the recognized tribes were established using a combination of FISH and conventional G- and C-banding. Our analyses allowed for the delimitation of three X chromosome types represented, respectively, by cattle (Bovinae, tribe Bovini), the tragelaphines (Bovinae, tribe Tragelaphini), and a large assemblage comprising all the remaining subfamilies and their tribes (the Cephalophinae, Hippotraginae, Alcelaphinae, Antilopinae, Aepycerotinae, Peleinae, and Caprinae). The use of the bacterial artificial chromosome probe BAC 101 (which maps to Xp12 in cattle) and an Xp painting probe comprising sequences specific for the short arm of cattle Xp (Xp24-->p12) allowed us to orient this region, which has moved as a conserved euchromatic block during the evolution of the bovid X chromosome. We show that the differences between the three chromosomal types are attributable to a transposition, two inversions, and heterochromatic additions/deletions. A paucity of comparative mapping data precludes the assignment of the sequences contained in cattle Xp to either the presumed conserved (XCR) or the recently added (XAR) region of the eutherian X chromosome, and the reasons for the retention of these sequences as an evolutionarily conserved unit in the intrachromosomal restructuring of the bovid X across lineages remain enigmatic.


Assuntos
Inversão Cromossômica , Cromossomo X , Animais , Antílopes/genética , Evolução Biológica , Bovinos , Bandeamento Cromossômico , Hibridização in Situ Fluorescente , Filogenia , Ovinos/genética
20.
Genomics ; 48(3): 314-23, 1998 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9545636

RESUMO

Carnitine palmitoyltransferase I (CPT-I) is a key enzyme involved in the regulation of fatty acid oxidation. CPT-IA and CPT-IB are isoforms of carnitine palmitoyltransferase I, of which CPT-IA is expressed in liver, kidney, fibroblasts, and heart and CPT-IB is expressed in skeletal muscle, heart, brown and white adipocytes, and testes. Although the genomic DNA sequence of human CPT-IB is available, the transcription start site and upstream regulatory sequences are not known. For rat CPT-IB, only the cDNA sequence has been published. We have cloned the entire rat CPT-IB gene from a Lambda fix II rat kidney genomic library. The genomic structure contains 19 exons, with the transcription start site for CPT-IB located in a short first exon, which is a 13-bp extension to the previously published cDNA 5' sequence. The coding sequence is identical with the rat muscle cDNA. The rat CPT-IB gene contains 18 introns and 19 exons, the latter 18 exons showing 85% homology to the human CPT-IB cDNA. CPT-IB maps to rat chromosome 7 at band q34. A putative promoter region was identified to within 391 bp of the transcription start site. The muscle specificity of the 5' flanking region was verified by comparison of luciferase expression to that of beta-galactosidase in cardiac myocytes and in HepG2 cells.


Assuntos
Carnitina O-Palmitoiltransferase/genética , Mapeamento Cromossômico , Músculo Esquelético/enzimologia , Regiões Promotoras Genéticas , Animais , Sequência de Bases , Genes Reporter , Humanos , Hibridização In Situ , Isoenzimas/genética , Dados de Sequência Molecular , Miocárdio/citologia , Miocárdio/enzimologia , Reação em Cadeia da Polimerase , Ratos , Análise de Sequência de DNA , Transcrição Gênica , Transfecção
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