This article may be too technical for most readers to understand.(April 2019) |
DXZ4 is a variable number tandemly repeated DNA sequence. In humans it is composed of 3kb monomers containing a highly conserved CTCF binding site. CTCF is a transcription factor protein and the main insulator responsible for partitioning of chromatin domains in the vertebrate genome. [1]
In addition to being enriched in CpG-islands, [2] DXZ4 transcribes long non-coding RNAs ( lncRNAs) and small RNAs of unknown function. [3] [4] Repeat copy number of DXZ4 is highly polymorphic in human populations (varying between 50 and 100 copies). DXZ4 is one of many large tandem repeat loci defined as macrosatellites. [2] Several macrosatellites have been described in humans and share similar features, such as high GC content, large repeat monomers, and high variability for repeat copy number within populations. [2] DXZ4 plays an important role in the unique structural conformation of the inactive X chromosome (Xi) in female somatic cells by acting as a hinge point between two large “super domains”. [5]
In addition to acting as the primary division between domains, DXZ4 forms long-range interactions with a number of other repeat rich regions along the inactive X chromosome. [6] Knockout of the DXZ4 locus revealed loss of this structural conformation on the Xi with chromosome wide silencing being maintained. [7]
This article may be too technical for most readers to understand.(April 2019) |
DXZ4 is a variable number tandemly repeated DNA sequence. In humans it is composed of 3kb monomers containing a highly conserved CTCF binding site. CTCF is a transcription factor protein and the main insulator responsible for partitioning of chromatin domains in the vertebrate genome. [1]
In addition to being enriched in CpG-islands, [2] DXZ4 transcribes long non-coding RNAs ( lncRNAs) and small RNAs of unknown function. [3] [4] Repeat copy number of DXZ4 is highly polymorphic in human populations (varying between 50 and 100 copies). DXZ4 is one of many large tandem repeat loci defined as macrosatellites. [2] Several macrosatellites have been described in humans and share similar features, such as high GC content, large repeat monomers, and high variability for repeat copy number within populations. [2] DXZ4 plays an important role in the unique structural conformation of the inactive X chromosome (Xi) in female somatic cells by acting as a hinge point between two large “super domains”. [5]
In addition to acting as the primary division between domains, DXZ4 forms long-range interactions with a number of other repeat rich regions along the inactive X chromosome. [6] Knockout of the DXZ4 locus revealed loss of this structural conformation on the Xi with chromosome wide silencing being maintained. [7]