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Bach2 is a B-cell-and neuron-specific transcription repressor that forms heterodimers with theEukaryotic genes are most often regulated by the simultaneous, synergistic activity of several transcription factors. Protein-protein interactions play important roles in synergistic activity among these factors. In this respect, the BTB/POZ domain (2, 4, 43) may be of particular interest because of its recurrent presence in transcription factors and its activity with regard to directing specific interactions. The genome project of Caenorhabditis elegans revealed that worms possess more than 100 genes that code for BTB/POZ domain proteins. Thus the BTB/POZ domain constitutes one of the largest families of protein domains in multicellular organisms (10). Interestingly, transcription factors encoding this domain are thought to play a variety of structural and organizational roles (1,2,4,13,21,34,35). For example, the Drosophila GAGA factor is involved in chromatin remodeling and in mediating enhancer-promoter interactions (34). Alterations of the PLZF and BCL6 genes, both encoding BTB/POZ factors, are associated with oncogenesis (9, 41). BTB/POZ domains appear to direct specific protein-protein interactions. However, the exact significance of such interactions in transcription regulation remains unclear.The mammalian transcription factors Bach1 and Bach2 (36) belong to the CNC-related bZip factors that include the hematopoietic factors NF-E2 p45 (3), Nrf1 (6,7,28), Nrf2 (18,31), and Nrf3 (24). Among these factors, Bach1 and Bach2 are unique in that they each possess a BTB/POZ domain. The CNC-related factors form heterodimers with the Maf-related factors through the leucine zippers and bind to the DNA sequence motif called MARE, which contains an AP-1 binding sequence. MARE is found in regulatory regions of various genes like ␤-globin genes, immunoglobulin heavy-chain genes, antioxidant response genes (e.g., GST genes), and crystallin genes (20). These observations suggest that transcription factors binding to the MARE may play important roles in a variety of vertebrate cell types and that only very few of the actual target genes of the CNC family have been identified.Among the CNC-related factors, Bach1 and Bach2 function as transcription repressors. In B cells, Bach2 represses the immunoglobulin heavy-chain 3Ј enhancer, or LCR, perhaps through binding to the corepressor SMRT (32). Since Bach2 possesses the BTB/POZ domain in the N terminus, it may regulate gene expression by interacting with other factors through the BTB/POZ domain. In this study, we identified a new BTB/POZ domain factor, MAZR, which associates with Bach2 through the BTB/POZ domain. MAZR stimulated transcription despite of its lack of any apparent transcription activation domain. Rather, BTB/POZ-mediated oligomer formation was important for transcriptional activity, suggesting that MAZR might be not a typical transactivator but an architectural transcription factor like Drosophila GAGA factor (21). Together with previous observations, our results suggest...

A hydroxyl ion assisted alcohol reduction method has been applied for the preparation of copper nanoparticles with an average diameter of 10.5 nm and narrow size distribution. The addition of specific amounts of hydroxyl ions to the alcoholic solution is the key to enhance the reducing potential of alcohols to obtain metal copper from their salts even with 1-butanol. The synthesis of copper metal was realized through intermediate steps corresponding to the formation of copper oxides (CuO and Cu 2 O). The obtained nanoparticles were coated with necessary surfactants and dispersed in organic solvent such as dodecane to prepare conducting ink. Samples annealed at 250 C in nitrogen and vacuum atmosphere showed electrical resistivity of 26 and 35 mU cm, respectively.

A modified polyol process for the synthesis of cubic‐shaped FeCo particles at 403 K is demonstrated. Control of the particle composition and size was achieved by varying the experimental conditions. The Fe content in the FeCo particles can be varied from 90 to 20 mol %, and the size of the cubes can be controlled to obtain particles with sizes between 300 and 35 nm (see figure). The magnetic properties of the particles closely resemble those of bulk FeCo.

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