Department of Molecular Medicine, The Herbert Wertheim University of Florida Scripps Institute for Biomedical Innovation and Technology, Jupiter, FL, USA; Department of Immunology and Microbiology, The Herbert Wertheim University of Florida Scripps Institute for Biomedical Innovation and Technology, Jupiter, FL, USA; Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, Jupiter, FL, USA.
Department of Molecular Medicine, The Herbert Wertheim University of Florida Scripps Institute for Biomedical Innovation and Technology, Jupiter, FL, USA; Department of Immunology and Microbiology, The Herbert Wertheim University of Florida Scripps Institute for Biomedical Innovation and Technology, Jupiter, FL, USA.
Cell Rep. 2024 Sep 24;43(9):114694. doi: 10.1016/j.celrep.2024.114694. Epub 2024 Aug 27.
Subgenomic flavivirus RNAs (sfRNAs) are structured RNAs encoded by flaviviruses that promote viral infection by inhibiting cellular RNA decay machinery. Herein, we analyze sfRNA production and localization using single-molecule RNA fluorescence in situ hybridization (smRNA-FISH) throughout West Nile virus, Zika virus, or dengue virus serotype 2 infection. We observe that sfRNAs are generated during the RNA replication phase of viral infection in the cytosol and accumulate in processing bodies (P-bodies), which contain RNA decay machinery such as XRN1 and Dcp1b. However, upon activation of the host antiviral endoribonuclease, ribonuclease L (RNase L), sfRNAs re-localize to ribonucleoprotein complexes known as RNase L-induced bodies (RLBs). RLB-mediated sequestration of sfRNAs reduces sfRNA association with RNA decay machinery in P-bodies, which coincides with increased viral RNA decay. These findings establish a functional role for RLBs in enhancing the cell-mediated decay of viral RNA by sequestering functional viral RNA decay products.
亚基因组黄病毒 RNA（sfRNA）是黄病毒编码的具有特定结构的 RNA，能够通过抑制细胞 RNA 降解机制来促进病毒感染。在此，我们通过单分子 RNA 荧光原位杂交（smRNA-FISH）分析西尼罗河病毒、寨卡病毒或登革热病毒 2 型感染过程中的 sfRNA 产生和定位。我们观察到，sfRNA 是在病毒感染的 RNA 复制阶段在细胞质中产生的，并在包含 RNA 降解机制（如 XRN1 和 Dcp1b）的处理体（P 体）中积累。然而，一旦宿主抗病毒内切核酸酶核糖核酸酶 L（RNase L）被激活，sfRNA 就会重新定位于称为 RNase L 诱导体（RLB）的核糖核蛋白复合物中。RLB 介导的 sfRNA 隔离会减少 sfRNA 与 P 体中 RNA 降解机制的结合，这与病毒 RNA 降解的增加相一致。这些发现确立了 RLB 在通过隔离功能性病毒 RNA 降解产物来增强细胞介导的病毒 RNA 降解中的功能作用。
