@misc{oai:ir.soken.ac.jp:00001012, author = {金, 麗華 and キン, レイカ and JIN, Liuha}, month = {2016-02-17}, note = {Living things increase their biological diversity by variable evolutionary mechanisms. Among these mechanisms, gene duplication and alternative splicing (A.S.) are the two major evolutionary routes that can bring the functional variation by increasing gene diversification. My research interest is to study about the evolutionary relationship between the two different phenomena by utilizing available all data resources. Results of this study showed that the percentage of A.S. locus in the singleton gene group was less than that in the duplicated gene group and the duplicate genes tended to have more A. S. isoforms than singleton genes. The results suggested that gene duplication would induce more alternative splicing events on the duplicate genes than on singletons possibly by reducing the functional constraint on the duplicates. process.
 The RNA-mediated gene silencing pathways are evolutionarily conserved. RNA interference is a widespread silencing mechanisms. Multicellular eukaryotes produce small RNA molecules (approximately 21-24 nuleotides) of two general types, miRNA and siRNA. They collectively function as sequence-specific guides to silence or regulate genes, transposons, and viruses and to modify chromatin and genome structure. This highlights a fundamental role of short RNAs in eukatyotic gene regulation and antiviral defense. Recently, 3 distinct small RNA directed silencing pathways are observed, such as the destruction of mRNA via siRNA, inhibition of mRNA translation via miRNA, and Epigenetic gene silencing via siRNA. It was also found that in these pathways the members of ribonclease III family play important role in diverse RNA maturation and decay. Here I investigated the evolution of Rnase III nucleases, Dicer as representative, to further figure out the evolutionary relations of 3 gene silencing pathways. And with the advantage of using genomic sequence as the subject, I also could detect some possible candidates for a particular functional domain or gene in un-annotated genomic region., and on the other hand, it can make more sure the judgement of Non-Existence of domain or gene in some species., 総研大甲第870号}, title = {Evolutionary processes of gene splicing and gene silencing}, year = {} }