Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Published: February 2009
AI Article Synopsis
Article Abstract
Heterochromatin is dynamically regulated during the cell cycle and in response to developmental signals. Recent findings from diverse systems suggest an extensive role for transcription in the assembly of heterochromatin, highlighting the emerging theme that transcription and noncoding RNAs can provide the initial scaffold for the formation of heterochromatin, which serves as a versatile recruiting platform for diverse factors involved in many cellular processes.
The recruitment of Heterochromatin Protein 1 (HP1) partners is essential for heterochromatin assembly and function, yet our knowledge regarding their organization in heterochromatin remains limited. Here we show that interactors engage the Drosophila HP1 (HP1a) dimer through a degenerate and expanded form of the previously identified PxVxL motif, which we now term HP1a Access Codes (HACs). These HACs reside in disordered regions, possess high conservation among Drosophila homologs, and contain alternating hydrophobic residues nested in a cluster of positively charged amino acids.
Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK; Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge CB2 0AW, UK. Electronic address:
The Human Silencing Hub (HUSH) guards the genome from the pathogenic effects of retroelement expression. Composed of MPP8, TASOR, and Periphilin-1, HUSH recognizes actively transcribed retrotransposed sequences by the presence of long (>1.5-kb) nascent transcripts without introns.
Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. Electronic address:
Researchers tackled the challenge of studying structural variants (SVs) in repetitive genomic regions using advanced technologies like long-read sequencing and the gapless T2T assembly.
They successfully analyzed 13 complex cases, resolving 10 by identifying specific genomic breakpoints and structures that were previously difficult to sequence, including Robertsonian translocations and ring chromosomes.
The study highlighted new mechanisms for SV formation and provided insights into how these genome variations affect gene expression and potential implications for disease diagnosis and genome biology.
Eukaryotic genomes, like those in humans, often contain large arrays of satellite DNA, such as Human Satellite 3 (HSat3), that are not well understood, especially in terms of their function outside of centromere biology.
HSat3 comprises about 2% of the human genome, forms massive arrays, and has been largely excluded from genomic studies until recently, leading to a lack of knowledge about its functional roles.
Recent research uncovered that HSat3 has a high density of transcription factor (TF) motifs, particularly related to the Hippo signaling pathway, and reveals that the TEAD transcription factor interacts with the co-activator YAP at HSat3 regions, suggesting a novel link between
Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; Graduate School of Biomedical Sciences, UT MD Anderson Cancer Center UTHealth Houston, Houston, TX, USA. Electronic address:
Mammalian retrotransposons constitute 40% of the genome. During tissue regeneration, adult stem cells coordinately repress retrotransposons and activate lineage genes, but how this coordination is controlled is poorly understood. Here, we observed that dynamic expression of histone methyltransferase SETDB1 (a retrotransposon repressor) closely mirrors stem cell activities in murine skin.
