Project report
終止コドンリードスルー配列の網羅的な特徴解析
政策・メディア研究科 修士課程2年 佐藤みさき
Abstract
Recent works suggest
that readthrough of stop codons can be one of the translation regulation
controls, but its mechanism is still unclear especially in eukaryotes. From the
latest study, we found that there may be several species-wide sequence
characteristics in the 3' untranslated region (3’UTR) of readthrough genes,
even though the factors or mechanisms to induce the event are different.
Therefore, in this study, we hypothesized that 3'UTR of these readthrough genes
have specific codon preferences similar to CDS comparing to those of regular
genes. We examined CDS, 3'UTR of regular genes, and 3'UTR of known readthrough
genes, and found that CDS and 3'UTR of regular genes have difference in codon
preferences. However, many 3'UTR sequences of known readthrough genes had
similarity to CDS, not to 3'UTR of regular genes. These results suggest that
3'UTR sequences which are synthesized by readthrough event use more optimal
codons which are highly efficient for translation than the other regular genes
whose 3'UTR are usually untranslated. Especially, codons whose 3rd position are
Cytosine and code polar but uncharged amino acids such as ACC(Threonine), GGC(Glycine), and
AGC(Serine) were well observed, suggesting the chemical specificity in
conformation or binding to ribosome in readthrough event. These specific
sequence characteristics in 3’UTR of readthrough genes may be widely preserved
among many species, and the identification of these characteristics could be
one of the important studies to understand stop codon readthrough.