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For the last couple of years, a method that permits the collection of precise positional information of transcriptional start sites (TSSs) together with digital information of the gene-expression levels in a high-throughput manner was established. We applied this novel method, ‘tss-seq’, to elucidate the transcriptome of tachyzoites of the Toxoplasma gondii, which resulted in the identification of 124 000 TSSs, and they were clustered into 10 000 transcription regions (TRs) with a statistics-based analysis. The TRs and annotated ORFs were paired, resulting in the identification of 30% of the TRs and 40% of the ORFs without their counterparts, which predicted undiscovered genes and stage-specific transcriptions, respectively. The massive data for TSSs make it possible to execute the first systematic analysis of the T. gondii core promoter structure, and the information showed that T. gondii utilized an initiator-like motif for their transcription in the major and novel motif, the downstream thymidine cluster, which was similar to the Y patch observed in plants. This encyclopaedic analysis also suggested that the TATA box, and the other well-known core promoter elements were hardly utilized. [ABSTRACT FROM PUBLISHER]

We characterized the DNA methylation status at 144 tissue-biased and 37 non-tissue-biased alternative promoters of 61 human genes in five normal tissues. Analysis of the collected data revealed that (i) DNA methylation status differed greatly among alternative promoters belonging to the same gene; (ii) DNA methylation status differed between tissues for the majority of the individual promoters, and (iii) 80–90% of CpG-island-containing promoters were not methylated on either allele throughout the five tissues examined. Furthermore, although the statistical significance was not as clear as for the above features, we also found that (iv) the DNA methylation patterns of tissue-biased promoters changed more drastically than those of non-tissue-biased promoters; (v) tissue-biased promoters tended to be less methylated than their respective alternative promoters in the tissues where they were preferentially expressed, and (vi) the ‘null’ methylation pattern of a given promoter was enriched in the tissues where the transcription was most active. These findings together indicate that there are dynamic physiological changes of DNA methylation. DNA methylation appears to play a significant role in differential usage of alternative promoters and may be related to functional diversification between CpG-island-containing promoters and CpG-island-less promoters. [ABSTRACT FROM PUBLISHER]