Core Viewpoint - The article discusses the significant findings of a research study on long non-coding RNA (lncRNA), specifically the structure of natural RNA nanocages formed by the ROOL RNA, which may have implications for research and therapeutic applications [2][3][11]. Group 1: Research Findings - The study identified two types of natural RNA nanocages formed by the long non-coding RNA ROOL found in bacterial and phage genomes [5]. - The cryo-EM structure revealed that the ROOL RNA forms an octameric nanocage with a diameter of 28 nanometers and an axial length of 20 nanometers, featuring a disordered region in its internal cavity [7]. - The assembly of the nanocage involves a chain exchange mechanism, leading to the formation of a quaternary kissing loop [7]. Group 2: Structural Characteristics - The octameric structure is stabilized by numerous tertiary and quaternary interactions, including the proposed "A-minor staple" [7]. - The isolated ROOL monomer structure was observed at a resolution of approximately 3.2 Å, indicating the complexity of the nanocage assembly [7]. Group 3: Potential Applications - The research suggests that ROOL RNA, when fused with RNA aptamers, tRNA, or microRNA, can maintain its structure and form a nanocage capable of radially displaying cargo [9]. - These findings may lead to the design of novel RNA nanocages for use as RNA carriers in research and therapeutic applications [11].