Abstract 5613: Study of long non-coding RNA TUG1 kinetics under replication stress conditions in cancer cell

Abstract

Abstract Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides that are not translated into proteins. In contrast to protein-coding mRNAs, certain lncRNAs carry out their functions within the nucleus. A detailed elucidation of the kinetics of lncRNAs contributes to a comprehensive understanding of their bona fide biological characteristics. Consequently, advancements in the in vivo visualization of lncRNAs have continued. Currently, various techniques, including RNA imaging technologies, have been employed to facilitate real-time tracking and visualization of RNA molecules within living cells. Taurine upregulated gene 1 (TUG1) is an oncogenic lncRNA, playing a pivotal role in cancer cells by resolving R-loops formed at stalled replication forks, particularly under replication stress conditions such as Hydroxyurea (HU) treatment. Despite its significance, the dynamic regulation of TUG1 under replication stress conditions remains largely unknown. In this study, we developed a stem loop-based live imaging system enabling real-time visualization of TUG1, providing insights into its subcellular localization and dynamic roles in physiological contexts. Upon treatment with HU, a chemical that interferes with replication, TUG1 expression was rapidly upregulated in the nucleus within 20 minutes. Additionally, we observed TUG1 molecules relocating close to the nuclear membrane. Considering the reported relocation of collapsed forks to the nuclear pore complex, this suggests that TUG1 may be involved in this relocation structure. These data indicate that TUG1 is associated with the fork restore mechanism occurring at the relocated collapsed forks, and the current live-cell imaging system holds potential for further uncovering the critical roles of TUG1 in cancer cells. Our stem loop-based imaging may contribute to a more precise understanding of RNA dynamics in live cells. Citation Format: Tomoya Fujita, Miho Suzuki, Osamu Masui, Keiko Shinjo, Yutaka Kondo. Study of long non-coding RNA TUG1 kinetics under replication stress conditions in cancer cell [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5613.