Biomedical subjects

Sahohime Matsumoto

Publications and source records attributed to Sahohime Matsumoto.

5 recordsLinked to original sources

PubMed2007

Genome-wide sreening by using small-interfering RNA expression libraries.

RNA interference (RNAi) is an evolutionarily conserved phenomenon in which gene expression is silenced by double-stranded RNA (dsRNA) in a sequence-specific manner. This technology has the potential to affect all aspects of target discovery and validation. With the completion of the human genome, it is now possible to design small-interfering RNA (siRNA) libraries targeting every human gene. Specific siRNAs, libraries containing a pathway, gene family, or gene set of interest, are expected to unsecure new targets in pathways of therapeutic interest. Here, we highlight the potential of siRNA screens for target identification by using cell-based assays.

Apoptosis↗

PubMed2005

Analysis of double-stranded RNA-induced apoptosis pathways using interferon-response noninducible small interfering RNA expression vector library.

We have developed an original vector library that allowed us to exploit the phenomenon of RNA interference but also allowed us to avoid the confounding effects of the interferon response. In the present work, we used our library of small interfering RNA expression vectors to examine the genes involved in apoptosis that was induced by double-stranded RNA. To our surprise, screening of our library revealed two novel double-stranded RNA-induced apoptotic pathways, a JNK/SAPK-mediated mitochondrial pathway and an ERK2-related pathway, both of which appeared to be independent of the serine-threonine protein kinase-dependent caspase pathway. We also found that MST2 and protein kinase Calpha both activated the pro-apoptotic signal mediated by ERK2. The results of our screening analysis suggested the utility of large scale screenings with libraries of small interfering RNA expression vectors.

Apoptosis↗

PubMed2005

Gene discovery by ribozyme and siRNA libraries.

Catalytic RNAs, also known as ribozymes, can be engineered to optimize their activities in the intracellular environment. The introduction of a library of active ribozymes into cells, and the subsequent screening for phenotypic changes, allows the rapid identification of gene function. For the determination of gene function, ribozyme technology complements another RNA-based tool that is based on libraries of small interfering RNAs.

Animals↗

PubMed2005

Chemistry-based RNA technologies: demonstration of usefulness of libraries of ribozymes and short hairpin RNAs (shRNAs).

Mechanism of action of hammerhead ribozymes has been investigated and their intracellular activities have been improved. Based on the improved ribozymes and more recently discovered natural RNAi, we have created libraries of both ribozymes and short hairpin RNAs (shRNAs). The introduction of a library of active ribozymes or shRNAs into cells, and the subsequent screening for phenotypic changes, allows the rapid identification of gene function.

Animals↗

PubMed2004

Generation of an shRNAi expression library against the whole human transcripts.

RNA interference is a phenomenon in which expression of an individual gene can be specifically silenced by introducing a double-stranded RNA, homologous to the gene, and is receiving attention as a powerful tool for reverse genetics in the post-genome era. Throughout our current research to generate an siRNA expression library for the whole human genome, we face many technical difficulties. We present here the strategies for overcoming some of the difficulties, including the development of genetically stable and highly active siRNA expression vectors, the selection procedure of the favorable target sites, and the efficient and low cost procedure for constructing an siRNA expression library. Furthermore, we demonstrate that the screening using the constructed siRNA-expression library indeed works, by evaluating siRNA-expression library against apoptosis-related genes.

Algorithms↗