RNA, being transcribed from DNA, has been considered as an intermediate step for the protein synthesis via mRNA. Besides mRNA which contains the genetic information, however, the fact that about 95% of RNA is remained untranslated is newly recognized. ...
RNA, being transcribed from DNA, has been considered as an intermediate step for the protein synthesis via mRNA. Besides mRNA which contains the genetic information, however, the fact that about 95% of RNA is remained untranslated is newly recognized. Because of this, the importance of the study on the non-coding RNA has emerged. In particular, although the ribosomal RNA (rRNA), which consist of 1500-3000 nucleotides, plays very important role in the protein synthesis as an enzyme, it has been difficult to analyze its structure because of its size. Previous studies on the structure of rRNA are mainly composed of the theoretical study such as the co-variation analysis in the comparative sequence analysis, and experimental study such as the x-ray crystallography. Most of these studies, however, focused on the qualitative aspect and unraveled such characteristics as the general structure of the molecule, the binding sites of mRNA and tRNA, and the sequence motif. However, these studies have a limit finding better specific characteristics of rRNA. Therefore, in order to find detail structural as well as functional characteristics of rRNA, it is necessary to perform additional studies from the quantitative perspective in addition to the qualitative studies. In this respect, the quantitative studies on the structure lead to a deeper analysis and will provide the basis for the more accurate understanding of the rRNA functions including the protein synthesis mechanism. In this study, we construct four networks of the secondary and tertiary structure of both Thermus thermophilus 16S rRNA and Haloarcula marismortui 23S rRNA. With the networks, we applied the complex network theory from the mathematics and computer science and various quantitative methods from the statistical physics to unravel their structural characteristics in terms of its function and rRNA folding problem.