Regulated transcription controls the diversity, developmental pathways and spatial organization of the hundreds of cell types that make up a mammal. Using single-molecule cDNA sequencing, we mapped transcription start sites (TSSs) and their usage in human and mouse primary cells, cell lines and tissues to produce a comprehensive overview of mammalian gene expression across the human body. We find that few genes are truly ‘housekeeping’, whereas many mammalian promoters are composite entities composed of several closely separated TSSs, with independent cell-type-specific expression profiles. TSSs specific to different cell types evolve at different rates, whereas promoters of broadly expressed genes are the most conserved. Promoter-based expression analysis reveals key transcription factors defining cell states and links them to binding-site motifs. The functions of identified novel transcripts can be predicted by coexpression and sample ontology enrichment analyses. The functional annotation of the mammalian genome 5 (FANTOM5) project provides comprehensive expression profiles and functional annotation of mammalian cell-type-specific transcriptomes with wide applications in biomedical research.

In the FANTOM5 project, transcription initiation events across the human and mouse genomes were mapped at a single base-pair resolution and their frequencies were monitored by CAGE (Cap Analysis of Gene Expression) coupled with single-molecule sequencing. Approximately three thousands of samples, consisting of a variety of primary cells, tissues, cell lines, and time series samples during cell activation and development, were subjected to a uniform pipeline of CAGE data production. The analysis pipeline started by measuring RNA extracts to assess their quality, and continued to CAGE library production by using a robotic or a manual workflow, single molecule sequencing, and computational processing to generate frequencies of transcription initiation. Resulting data represents the consequence of transcriptional regulation in each analyzed state of mammalian cells. Non-overlapping peaks over the CAGE profiles, approximately 200,000 and 150,000 peaks for the human and mouse genomes, were identified and annotated to provide precise location of known promoters as well as novel ones, and to quantify their activities.

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We report the crystal structures, magnetic susceptibilities and thermoelectric properties of a delafossite-type oxide, CuCr1-xMgxO2 (0 ≤x ≤0.05) at temperatures in the range from 4 to 1100 K. The lattice parameter, c, linearly decreases with increasing Mg concentration in the range 0 ≤x ≤0.03. This decrease is mainly caused by the shrinking of O–Cu–O dumbbells which connect the CdI2-type (Cr/Mg)O2 slabs. Magnetic susceptibility measurements indicate that Cr3+ is in the high spin state in the paramagnetic phase above 25 K. The electrical resistivity, ρ, of CuCr1-xMgxO2 exhibits semiconducting behavior (dρ/dT < 0) in the range from 350 to 1100 K, which decreases through the partial substitution of Mg2+ for Cr3+ with 0 ≤x ≤0.03. Positive and high Seebeck coefficients of CuCr1-xMgxO2 at high temperatures are consistant with the theoretical values predicted by Koshibae, who considered the spin entropy flux for the high-temperature Seebeck coefficent. From the linear S vs ln σ plot, considerable contribution from the band structure and carrier concentraton to the Seebeck coefficient is indicated. The power factor, S2σ, reaches its maximum value at around x = 0.03 in this system. The thermal conductivity, κ, for CuCr1-xMgxO2 ranges from 6 to 10 W·m-1·K-1 at 300 K, slowly decreasing with increasing temperature up to 1000 K. In the present system, the maximum dimensionless figure of merit, ZT=S2T/ρκ= 0.04, is realized for the case of x = 0.03 at 950 K.

The electric manipulation of antiferromagnets has become an area of great interest recently for zero-stray-field spintronic devices, and for their rich spin dynamics. Generally, the application of antiferromagnetic media for information memories and storage requires a heterostructure with a ferromagnetic layer for readout through the exchange-bias field. In magnetoelectric and multiferroic antiferromagnets, the exchange coupling exerts an additional impediment (energy barrier) to magnetization reversal by the applied magnetoelectric energy. We proposed and verified a method to overcome this barrier. We controlled the energy required for switching the magnetic domains in magnetoelectric Cr 2 O 3 films by compensating the exchange-coupling energy from the ferromagnetic layer with the Zeeman energy of a small volumetric spontaneous magnetization found for the sputtered Cr 2 O 3 films. Based on a simplified phenomenological model of the field-cooling process, the magnetic and electric fields required for switching could be tuned. As an example, the switching of antiferromagnetic domains around a zero-threshold electric field was demonstrated at a magnetic field of 2.6 kOe.