Publications by authors named "Hiromi Nishiyori"

Article Synopsis
  • Long-read RNA sequencing is crucial for accurate eukaryotic genome annotation, but consistent identification of RNA transcripts is still challenging.
  • CapTrap-seq is a new cDNA library preparation method that enhances detection of full-length RNA transcripts by using a Cap-trapping strategy and oligo(dT) priming.
  • In tests comparing CapTrap-seq to other RNA-seq methods on human and mouse tissues, results show it effectively reconstructs full-length RNA molecules and performs well across various sequencing platforms.
View Article and Find Full Text PDF

Long-read RNA sequencing is essential to produce accurate and exhaustive annotation of eukaryotic genomes. Despite advancements in throughput and accuracy, achieving reliable end-to-end identification of RNA transcripts remains a challenge for long-read sequencing methods. To address this limitation, we developed CapTrap-seq, a cDNA library preparation method, which combines the Cap-trapping strategy with oligo(dT) priming to detect 5'capped, full-length transcripts, together with the data processing pipeline LyRic.

View Article and Find Full Text PDF

In eukaryotes, capped RNAs include long transcripts such as messenger RNAs and long noncoding RNAs, as well as shorter transcripts such as spliceosomal RNAs, small nucleolar RNAs, and enhancer RNAs. Long capped transcripts can be profiled using cap analysis gene expression (CAGE) sequencing and other methods. Here, we describe a sequencing library preparation protocol for short capped RNAs, apply it to a differentiation time course of the human cell line THP-1, and systematically compare the landscape of short capped RNAs to that of long capped RNAs.

View Article and Find Full Text PDF
Article Synopsis
  • Long noncoding RNAs (lncRNAs) make up most of transcripts in mammalian genomes, but their functions are still not well understood.
  • The FANTOM6 project systematically knocked down 285 lncRNAs in human dermal fibroblasts and analyzed changes in cell growth, shape, and gene expression using CAGE techniques.
  • This study provides a comprehensive lncRNA knockdown data set (over 1000 CAGE sequencing libraries) and reveals important findings about their roles and impact on various cellular pathways.
View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

MicroRNAs (miRNAs) have been demonstrated to be potent post-trascriptional modulators of protein expression. miRNA expression was profiled in the left and right dorsal hippocampal CA3 of mature rats by high-throughput deep sequencing. Among the sequenced and cross-mapped small RNAs, 88% belonged to the miRNAs annotated in the miRBase 15 database.

View Article and Find Full Text PDF

The cap analysis of gene expression (CAGE) technology has been established to detect transcriptional starting sites (TSSs) and expression levels by utilizing 5' cDNA tags and PCR. It has been reported that the amount of templates is proportional to the amplification efficiency of PCR. CAGE has been used as a key technique for analyzing promoter activity and finding new transcripts including alternative spliced products and noncoding transcripts.

View Article and Find Full Text PDF

It has been reported that relatively short RNAs of heterogeneous sizes are derived from sequences near the promoters of eukaryotic genes. In conjunction with the FANTOM4 project, we have identified tiny RNAs with a modal length of 18 nt that map within -60 to +120 nt of transcription start sites (TSSs) in human, chicken and Drosophila. These transcription initiation RNAs (tiRNAs) are derived from sequences on the same strand as the TSS and are preferentially associated with G+C-rich promoters.

View Article and Find Full Text PDF

Using deep sequencing (deepCAGE), the FANTOM4 study measured the genome-wide dynamics of transcription-start-site usage in the human monocytic cell line THP-1 throughout a time course of growth arrest and differentiation. Modeling the expression dynamics in terms of predicted cis-regulatory sites, we identified the key transcription regulators, their time-dependent activities and target genes. Systematic siRNA knockdown of 52 transcription factors confirmed the roles of individual factors in the regulatory network.

View Article and Find Full Text PDF
Article Synopsis
  • Finding and mapping mRNAs and their transcription start sites (TSS) is crucial in post-genome biology, revealing that mammalian cells have far more TSS than previously thought.
  • The new high-throughput sequencing method, DeepCAGE, combines Cap Analysis of Gene Expression with ultra-high-throughput sequencing to characterize TSS from mouse hippocampus, resulting in 1.4 million sequenced TSS and the most comprehensive promoter data set to date.
  • The study provides insights into gene regulation in the hippocampus, highlighting the important role of the Arnt2 transcription factor, and demonstrates DeepCAGE's ability to identify promoters active in specific cell subsets within complex tissues.
View Article and Find Full Text PDF

CAGE (cap analysis of gene expression) is a method for identifying transcription start sites by sequencing the first 20 or 21 nucleotides from the 5' end of capped transcripts, allowing genome-wide promoter analyses to be performed. The potential of the CAGE as a form of expression profiling was limited previously by sequencing technology and the labor-intensive protocol. Here we describe an improved CAGE method for use with a next generation sequencer.

View Article and Find Full Text PDF

Animal-specific gene families involved in cell-cell communication and developmental control comprise many subfamilies with distinct domain structures and functions. They diverged by subfamily-generating duplications and domain shufflings before the parazoan-eumetazoan split. Here, we have cloned 40 PTK cDNAs from choanoflagellates, Monosiga ovata, Stephanoeca diplocostata and Codosiga gracilis, the closest relatives to animals.

View Article and Find Full Text PDF