Genome-wide Search for LINEl (LI) with Biological or Transcriptional Activity

Autor: Kamiyama, Satoko, Oda, Takaya, Jinno, Yoshihiro
Jazyk: japonština
Rok vydání: 2008
Předmět:
Zdroj: 琉球医学会誌 = Ryukyu Medical Journal. 27(1・2):11-18
ISSN: 1346-888X
Popis: One of research subjects in our laboratory is to elucidate roles of DNA methylation and retrotransposons in the pathogenesis of complex hereditary diseases/disorders, for example schizophrenia. So far we have identified several human endogenous retroviruses (HERVs) with transcriptional potential in the brain as well as those abundantly expressed in the placenta. In our current study we performed a genome-wide search for transcriptionally active long interspersed nuclear elements 1 (LINE1s; L1s) We adopted two different ways to find out them beginning the search with human expressed sequence tag (EST) and genome-DNA databases. The full-length Sequence of L1 3 (6,059 bp) was used as a query in the both cases. We collected 5,000 ESTs homologous to L1 3, mapped them to chromosomal L1 loci, and finally extracted 254 loci from which three and more ESTs were derived In the search of genome-DNA databases we found 5,134 L1 sequences homologous to L1 3 and downloaded them together with 1-kb flanking sequences. We finally narrowed down to 146 L1s that retained both of the ORF1- and ORF2-coding amino acid sequences. Some of these L1s were subjected to the first verification experiment using the RT-PCR, cloning, and sequencing method Two or more clones with identical sequences were found more frequently in RT-PCR than in genomic PCR The distribution of L1 subfamilies detected in PCR clones was apparently different between the two kinds of PCR These results suggested that RT-PCR detected some L1 loci different from genomic DNA in their frequency and that our current study should include something worth analyzing in further detail although the development of more efficient techniques is essential to the rapid and extensive progress of the study.
論文
Databáze: OpenAIRE