Abstract
Autoimmune regulator (AIRE) is responsible for the development of organ-specific autoimmune disease in a monogenic fashion. Rare and low levels of tissue expression together with the lack of AIRE-expressing cell lines have hampered a detailed analysis of the molecular dynamics of AIRE. Here we have established cell lines stably transfected with AIRE and studied the regulatory mechanisms for its subcellular expression. We found that nuclear body (NB) formation by AIRE was dependent on the cell cycle. Biochemical fractionation revealed that a significant proportion of AIRE is associated with the nuclear matrix, which directs the functional domains of chromatin to provide sites for gene regulation. Upon proteasome inhibition, AIRE NBs were increased with concomitant reduced expression in the cytoplasm, suggesting that subcellular targeting of AIRE is regulated by a ubiquitin-proteasome pathway. We also found that AIRE NBs compete for cAMP-response element-binding protein-binding protein/p300, a common coactivator of transcription, with the promyelocytic leukemia gene product. These results suggest that the transcriptional regulating activities of AIRE within a cell are controlled and organized in a spatiotemporal manner.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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AIRE Protein
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Animals
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Binding, Competitive
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Cell Nucleus / metabolism
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Cyclic AMP Response Element-Binding Protein / metabolism
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Cysteine Endopeptidases / metabolism
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DNA, Complementary / genetics
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E1A-Associated p300 Protein
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Enzyme Inhibitors / pharmacology
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Gene Expression Regulation*
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Green Fluorescent Proteins
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HeLa Cells
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Humans
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Immunohistochemistry
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Luminescent Proteins / genetics
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Mice
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Multienzyme Complexes / antagonists & inhibitors
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Multienzyme Complexes / metabolism
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NIH 3T3 Cells
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Neoplasm Proteins / metabolism
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Nuclear Proteins / metabolism
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Polymerase Chain Reaction
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Promyelocytic Leukemia Protein
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Proteasome Endopeptidase Complex
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Recombinant Fusion Proteins
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Subcellular Fractions / metabolism*
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Subcellular Fractions / ultrastructure
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Time Factors
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Trans-Activators / metabolism
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Transcription Factors / genetics*
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Transcription Factors / metabolism
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Transfection
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Tumor Suppressor Proteins
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Ubiquitin / metabolism
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Ubiquitin-Protein Ligases / metabolism
Substances
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Cyclic AMP Response Element-Binding Protein
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DNA, Complementary
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Enzyme Inhibitors
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Luminescent Proteins
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Multienzyme Complexes
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Neoplasm Proteins
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Nuclear Proteins
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Pml protein, mouse
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Promyelocytic Leukemia Protein
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Recombinant Fusion Proteins
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Trans-Activators
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Transcription Factors
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Tumor Suppressor Proteins
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Ubiquitin
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PML protein, human
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Green Fluorescent Proteins
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E1A-Associated p300 Protein
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Ep300 protein, mouse
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Ubiquitin-Protein Ligases
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Cysteine Endopeptidases
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Proteasome Endopeptidase Complex