Label core for understanding RNA structure

The RNA structure, the main predictor of biological function, is the result of the folding process. While the nucleotides in the RNA sequence rapidly coupled forming weak bonds, the spatial arrangement is a slow process. Although many computational approaches have been proposed to study the folding process of RNA, most of them do not consider the hierarchical aspect existing among the bonds. In this work, we propose to collapse nucleotides and bonds underpinning the primary and secondary structure of RNA in a unique label core congruent with the spatial configuration. A label core is represented as a term of generalized context-free grammar properly defined to support RNA structural reduction and analysis.