The ER repeat protein YT521-B localizes to a novel subnuclear compartment.
The characterization of distinct subnuclear domains suggests a dynamic nuclear framework supporting gene expression and DNA replication. Here, we show that the glutamic acid/arginine-rich domain protein YT521-B localizes to a novel subnuclear structure, the YT bodies. YT bodies are dynamic compartments, which first appear at the beginning of S-phase in the cell cycle and disperse during mitosis. Furthermore, in untreated cells of the human cell line MCF7 they were undetectable and appeared only after drug- induced differentiation. YT bodies contain transcriptionally active sites and are in close contact to other subnuclear structures such as speckles and coiled bodies. YT bodies disperse upon actinomycin D treatment, whereas other transcriptional inhibitors such as alpha-amanitin or DRB have little effect. On the basis of our experiments, we propose that YT521-B may participate in the assembly of genes into transcription centers, thereby allowing efficient regulation of gene expression.
Nayler
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Max-Planck-Institute of Neurobiology, Max-Planck-Institute of Biochemistry, D-82152 Martinsried, Germany. oliver.nayler@actelion.com
Hartmann
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Stamm
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D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies; D019556:COS Cells; D002453:Cell Cycle / Q000502:physiology*; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D006224:Cricetinae; D004261:DNA Replication; D003609:Dactinomycin / Q000494:pharmacology; D006801:Humans; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D009687:Nuclear Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry / Q000276:immunology; D000072260:RNA Splicing Factors; D016601:RNA-Binding Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000032:analysis; D020449:Repetitive Sequences, Amino Acid; D016196:S Phase; D014158:Transcription, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured
D000906:Antibodies; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D010446:Peptide Fragments; D000072260:RNA Splicing Factors; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; C490769:YTHDC1 protein, human; D003609:Dactinomycin