1. The nuclear import of TAF10 is regulated by one of its three histone fold domain-containing interaction partners
- Author
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Elisabeth Scheer, Máté Á. Demény, Laszlo Tora, Giulia Fienga, Evi Soutoglou, Paolo Sassone-Corsi, Institut de génétique et biologie moléculaire et cellulaire (IGBMC), and Université Louis Pasteur - Strasbourg I-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Male ,Cytoplasm ,Nuclear Localization Signals ,Gene Expression ,MESH: Nuclear Localization Signals ,MESH: Spermatocytes ,Diffusion ,Histones ,MESH: Protein Structure, Tertiary ,0302 clinical medicine ,Spermatocytes ,MESH: TATA-Binding Protein Associated Factors ,MESH: Histones ,0303 health sciences ,MESH: Transcription Factor TFIID ,MESH: Diffusion ,MESH: Transcription Factors ,MESH: Fatty Acids, Unsaturated ,beta Karyopherins ,Cell biology ,030220 oncology & carcinogenesis ,Fatty Acids, Unsaturated ,Transcription factor II D ,Protein Binding ,MESH: Cell Nucleus ,Active Transport, Cell Nucleus ,Importin ,MESH: Active Transport, Cell Nucleus ,Biology ,03 medical and health sciences ,Humans ,MESH: Protein Binding ,Molecular Biology ,Transcription factor ,030304 developmental biology ,Cell Nucleus ,TATA-Binding Protein Associated Factors ,MESH: Humans ,TATA-Box Binding Protein ,MESH: Cytoplasm ,[SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology ,Cell Biology ,Molecular biology ,MESH: Male ,Protein Structure, Tertiary ,MESH: Hela Cells ,Transcription Factor TFIID ,Nuclear transport ,MESH: beta Karyopherins ,Nuclear localization sequence ,HeLa Cells ,Transcription Factors - Abstract
International audience; TFIID, comprising the TATA box binding protein (TBP) and 13 TBP-associated factors (TAFs), plays a role in nucleation in the assembly of the RNA polymerase II preinitiation complexes on protein-encoding genes. TAFs are shared among other transcription regulatory complexes (e.g., SAGA, TBP-free TAF-containing complex [TFTC], STAGA, and PCAF/GCN5). Human TAF10, a subunit of both TFIID and TFTC, has three histone fold-containing interaction partners: TAF3, TAF8, and SPT7Like (SPT7L). In human cells, exogenously expressed TAF10 remains rather cytoplasmic and leptomycin B does not affect this localization. By using fluorescent fusion proteins, we show that TAF10 does not have an intrinsic nuclear localization signal (NLS) and needs one of its three interaction partners to be transported into the nucleus. When the NLS sequences of either TAF8 or SPT7L are mutated, TAF10 remains cytoplasmic, but a heterologous NLS can drive TAF10 into the nucleus. Experiments using fluorescence recovery after photobleaching show that TAF10 does not associate with any cytoplasmic partner but that once transported into the nucleus it binds to nuclear structures. TAF10 binding to importin beta in vitro is dependent on the coexpression of either TAF8 or TAF3, but not SPT7L. The cytoplasmic-nuclear transport of TAF10 is naturally observed during the differentiation of adult male germ cells. Thus, here we describe a novel role of the three mammalian interacting partners in the nuclear localization of TAF10, and our data suggest that a complex network of regulated cytoplasmic associations may exist among these factors and that this network is important for the composition of different TFIID and TFTC-type complexes in the nucleus.
- Published
- 2005