Our laboratory focuses on elucidating the functions of long non-coding 11tribute to therapeutic advances.RNAs (lncRNAs). We previously discovered a type of antisense lncRNA called SINEUPs that work specifically to enhance the production of proteins by binding to their target mRNAs. SINEUPs can be designed to amplify a spe-cific protein so that they are possible tools for developing therapies for diseases where a particular protein is insufficiently synthesized.In order to understand the molecular mechanisms of SINEUP activity, we investigated the interactions of SINEUPs with other molecules. Using RNA FISH, we found that SINEUPs localize to both the nucleus and cytoplasm, while mRNAs mainly localize to the cytoplasm, and that SINEUPs and mRNAs co-lo-calize in the cytoplasm. Then we performed ChIRP-MS analysis of proteins that bind to SINEUPs and mRNAs and the result showed that RNA binding proteins (RBPs), HNRNPK and PTBP1, form a complex at the co-localized sites. Over-expression of these RBPs enhanced the target protein production only when SINEUPs were present, suggesting that HNRNPK and PTBP1 form a complex with SINEUPs and functionally enhance the target protein production. From these results and loss- and gain-of-function studies of the RBPs, we found that the complex formation of SINEUPs and the RBPs enables the translocation of the SINEUPs from the cell nucleus to the cytoplasm, facilitates the initiation of the mRNA translation, and promotes the synthesis of the target proteins.The molecular structure of RNA is also important for elucidating its mecha-nism of function. Using NMR in collaboration with Dr. Yoshitaka Ishii’s group at RIKEN SPring-8 Center, we furthermore identified the secondary structure and the active site of a 167-nt inverted SINE B2, which is present in the effector domain of SINEUPs.These findings will promote a better understanding of SINEUPs and con-Figure: Model of SINEUP RNA and SINEUP RNA binding protein (RBP) interactionsSINEUP RBPs (PTBP1 and HNRNPK) participate in SINEUP RNA localization both in the nucleus and the cytoplasm. In the nucleus, some RNAs form RNA–protein granules (dotted circle) where immature transcripts with non-proper conformations likely accumulate to cluster, and mature transcripts including EGFP mRNA and SINEUP RNA form complexes with SINEUP RPBs. These com-plexes may then be shuttled into the cytoplasm. In the cytoplasm, SINEUP RNAs co-operate with the SINEUP RBPs, likely remodeling SINEUP RNA structure, and recruit ribosomal subunits to efficiently supply them to EGFP mRNA, resulting in the enhancement of EGFP mRNA translation. EGFP mRNA can be exported into the cytoplasm by itself, but its translation is initiated more efficiently when SINEUP-GFP mRNA is present.Recent Major PublicationsToki N, Takahashi H, Sharma H, Valentine MNZ, Rahman FM, Zucchelli S, Gustincich S, Carninci P. SINEUP long non-coding RNA acts via PTBP1 and HNRNPK to promote translational initiation assemblies. Nucleic Acids Res 48, 11626-11644 (2020)Toki N, Takahashi H, Zucchelli S, Gustincich S, Carninci P. Synthetic in vitro transcribed lncRNAs (SINEUPs) with chemical modifications enhance target mRNA transla-tion. FEBS Lett. 594, 4357-4369 (2020)Ohyama T, Takahashi H, Sharma H, Yamazaki T, Gustin-cich S, Ishii Y, Carninci P. An NMR-based approach reveals the core structure of the functional domain of SINEUP lncRNAs. Nucleic Acids Res. 48, 9346-9360 (2020)Invited presentationsCarninci P. “Identification of non-coding genome ele-ments at single-cell resolution for fine modulation of gene activity” Computational biology and artificial intelligence for personalized medicine (Russia/Online) September 2021Carninci P. “Why map every cell in the human body?” PNEUMOTRIESTE 2021 (Trieste, Italy/Online) September 2021Carninci P. “Growing role of regulatory RNAs in genomic medicine” SCIENCE & LAW International Law Answers to Scientists’ Current Challenges (Trieste, Italy/Online) September 2021Carninci P. “Long non-coding RNAs: from interactome to function” Noncoding RNA World: From Mechanism to Therapy (Switzerland/Online) July 2021Carninci P. “Cellular networks and their regulation using antisense lncRNAs” School of Biotechnology & Biomo-lecular Sciences at the University of New South Wales Online Seminar (Sydney, Australia/Online) April 2021Laboratory for Transcriptome TechnologyTeam Leader: Piero Carninci
元のページ ../index.html#17