Xist
Mostrando 1-12 de 48 artigos, teses e dissertações.
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1. Stability of XIST repression in relation to genomic imprinting following global genome demethylation in a human cell line
DNA methylation is essential in X chromosome inactivation and genomic imprinting, maintaining repression of XIST in the active X chromosome and monoallelic repression of imprinted genes. Disruption of the DNA methyltransferase genes DNMT1 and DNMT3B in the HCT116 cell line (DKO cells) leads to global DNA hypomethylation and biallelic expression of the imprin
Braz J Med Biol Res. Publicado em: 17/10/2014
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2. Início e manutenção da inativação do cromossomo X em células humanas / Establishment and maintenance of X-chromosome inactivation in human cells
Em fêmeas de mamíferos, um dos cromossomos X é inativado proporcionando compensação de dose entre os produtos gênicos de machos e fêmeas. A inativação do cromossomo X (ICX) ocorre no embrião em desenvolvimento, e se caracteriza pela aquisição de marcas heterocromáticas no cromossomo X inativado (Xi), que são mantidas nas células somáticas ao
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/04/2012
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3. Estabilidade do controle epigenético em células humanas normais e transformadas / Stability of epigenetic control in normal and transformed human cells
A epigenética aborda o controle da expressão gênica através de diversos fatores que agem sob a cromatina, os melhor estudados são a metilação do DNA e a acetilação em histonas, relacionadas à repressão e ativação gênica, respectivamente. Em mamíferos, existem dois fenômenos epigenéticos interessantes: a inativação do cromossomo X (ICX) em
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 20/03/2012
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4. Padrão de metilação dos genes IGF2 e XIST em ovócitos oriundos de folículos pré-antrais de vacas Nelore (Bos taurus indicus) / Methylation pattern of the IGF2 and XIST genes in oocytes obtained of the preantral follicles from Nellore cows (Bos taurus indicus)
Com o intuito de aumentar a produtividade, visando o máximo de aproveitamento do material genético disponível, várias biotecnologias reprodutivas vêm sendo desenvolvidas e utilizadas. Apesar de ovócitos obtidos de folículos pré-antrais não terem ainda competência para produzir embrião, são uma fonte muito importante de gametas a ser utilizada na
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 06/04/2011
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5. Estudo do padrão de inativação do cromossomo X em tecido extra-embrionário humano / X-chromosome inactivation pattern in human extra-embryonic tissue
Imprinted inactivation of the paternal X chromosome in marsupials is the primordial mechanism of dosage compensation for X-linked genes between females and males in Therians. In Eutherian mammals, X chromosome inactivation (XCI) evolved into a random process in cells from the embryo proper, where either the maternal or paternal X can be inactivated. However,
Publicado em: 2010
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6. Análise funcional dos genes Xist e DNMT1 na manutenção do processo de inativação do cromossomo X humano através do silenciamento gênico por RNAi / Functional analysis of XIST and DNMT1 genes in the maintenance of X chromosome inactivation process in human through gene silencing by RNAi
X chromosome inactivation (XCI) is the phenomenon through which one of the X chromosomes in female mammals is silenced to achieve dosage compensation related to males. It involves the expression of XIST gene exclusively from the inactive X, and the association of its RNA in cis in this chromosome. This leads to a series of epigenetic modifications in the chr
Publicado em: 2008
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7. Reactivation of XIST in normal fibroblasts and a somatic cell hybrid: Abnormal localization of XIST RNA in hybrid cells
The XIST gene, expressed only from the inactive X chromosome, is a critical component of X inactivation. Although apparently unnecessary for maintenance of inactivation, XIST expression is thought to be sufficient for inactivation of genes in cis even when XIST is located abnormally on another chromosome. This repression appears to involve the association of
The National Academy of Sciences.
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8. Human XIST yeast artificial chromosome transgenes show partial X inactivation center function in mouse embryonic stem cells
Initiation of X chromosome inactivation requires the presence, in cis, of the X inactivation center (XIC). The Xist gene, which lies within the XIC region in both human and mouse and has the unique property of being expressed only from the inactive X chromosome in female somatic cells, is known to be essential for X inactivation based on targeted deletions i
The National Academy of Sciences.
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9. Further examination of the Xist promoter-switch hypothesis in X inactivation: Evidence against the existence and function of a P0 promoter
The onset of X inactivation coincides with accumulation of Xist RNA along the future inactive X chromosome. A recent hypothesis proposed that accumulation is initiated by a promoter switch within Xist. In this hypothesis, an upstream promoter (P0) produces an unstable transcript, while the known downstream promoter (P1) produces a stable RNA. To test this hy
The National Academy of Sciences.
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10. Characterization of the Genomic Xist Locus in Rodents Reveals Conservation of Overall Gene Structure and Tandem Repeats but Rapid Evolution of Unique Sequence
The Xist locus plays a central role in the regulation of X chromosome inactivation in mammals, although its exact mode of action remains to be elucidated. Evolutionary studies are important in identifying conserved genomic regions and defining their possible function. Here we report cloning, sequence analysis, and detailed characterization of the Xist gene f
Cold Spring Harbor Laboratory Press.
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11. Induction of XIST expression from the human active X chromosome in mouse/human somatic cell hybrids by DNA demethylation.
X chromosome inactivation occurs early in mammalian development to transcriptionally silence one of the pair of X chromosomes in females. The XIST RNA, a large untranslated RNA that is expressed solely from the inactive X chromosome, is implicated in the process of inactivation. As previous studies have shown that the XIST gene is methylated on the active X
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12. Regulation of X-Chromosome Inactivation in Development in Mice and Humans
Dosage compensation for X-linked genes in mammals is accomplished by inactivating one of the two X chromosomes in females. X-chromosome inactivation (XCI) occurs during development, coupled with cell differentiation. In somatic cells, XCI is random, whereas in extraembryonic tissues, XCI is imprinted in that the paternally inherited X chromosome is preferent
American Society for Microbiology.