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Drosophila CTCF is required for Fab-8 enhancer blocking activity in S2 cells.

ABSTRACT: CTCF is a conserved transcriptional regulator with binding sites in DNA insulators identified in vertebrates and invertebrates. The Drosophila Abdominal-B locus contains CTCF binding sites in the Fab-8 DNA insulator. Previous reports have shown that Fab-8 has enhancer blocking activity in Drosophila transgenic assays. We now confirm the enhancer blocking capability of the Fab-8 insulator in stably transfected Drosophila S2 cells and show this activity depends on the Fab-8 CTCF binding sites. Furthermore, knockdown of Drosophila CTCF by RNAi in our stable cell lines demonstrates that CTCF itself is critical for Fab-8 enhancer blocking.

SUBMITTER: Ciavatta D

PROVIDER: S-EPMC2694738 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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Drosophila CTCF is required for Fab-8 enhancer blocking activity in S2 cells.

Ciavatta Dominic D Rogers Steve S Magnuson Terry T

Journal of molecular biology 20070814 2

CTCF is a conserved transcriptional regulator with binding sites in DNA insulators identified in vertebrates and invertebrates. The Drosophila Abdominal-B locus contains CTCF binding sites in the Fab-8 DNA insulator. Previous reports have shown that Fab-8 has enhancer blocking activity in Drosophila transgenic assays. We now confirm the enhancer blocking capability of the Fab-8 insulator in stably transfected Drosophila S2 cells and show this activity depends on the Fab-8 CTCF binding sites. Fur ...[more]

PMID: 17825318

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CTCF is conserved from Drosophila to humans and confers enhancer blocking of the Fab-8 insulator.

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