An Intronic Element Attenuates the Transcription of a Long Non-coding RNA in Human Cell Lines.

elements are primate-specific repeats and represent the most abundant type of transposable elements (TE) in the human genome. Genome-wide analysis of the enrichment of histone post-translational modifications suggests that human sequences could function as transcriptional enhancers; however, no functional experiments have evaluated the role of sequences in the control of transcription . The present study analyses the regulatory activity of a human sequence from the family located in the second intron of the long intergenic non-coding RNA , found in divergent orientation to the gene.

Epigenetic silencing of miR-181c by DNA methylation in glioblastoma cell lines.

Background: Post-transcriptional regulation by microRNAs is recognized as one of the major pathways for the control of cellular homeostasis. Less well understood is the transcriptional and epigenetic regulation of genes encoding microRNAs. In the present study we addressed the epigenetic regulation of the miR-181c in normal and malignant brain cells.

A novel chromatin insulator regulates the chicken folate receptor gene from the influence of nearby constitutive heterochromatin and the β-globin locus.

The three-dimensional architecture of genomes provides new insights about genome organization and function, but many aspects remain unsolved at the local genomic scale. Here we investigate the regulation of two erythroid-specific loci, a folate receptor gene (FOLR1) and the β-globin gene cluster, which are separated by 16kb of constitutive heterochromatin. We found that in early erythroid differentiation the FOLR1 gene presents a permissive chromatin configuration that allows its expression.

Experimental strategies to manipulate the cellular levels of the multifunctional factor CTCF.

Cellular homeostasis is the result of an intricate and coordinated combinatorial of biochemical and molecular processes. Among them is the control of gene expression in the context of the chromatin structure which is central for cell survival. Interdependent action of transcription factors, cofactors, chromatin remodeling activities, and three-dimensional organization of the genome are responsible to reach exquisite levels of gene expression.

Gain of DNA methylation is enhanced in the absence of CTCF at the human retinoblastoma gene promoter.

Background: Long-term gene silencing throughout cell division is generally achieved by DNA methylation and other epigenetic processes. Aberrant DNA methylation is now widely recognized to be associated with cancer and other human diseases. Here we addressed the contribution of the multifunctional nuclear factor CTCF to the epigenetic regulation of the human retinoblastoma (Rb) gene promoter in different tumoral cell lines.