CryoEM reveals that ribosomes in microsporidian spores are locked in a dimeric hibernating state

作者：Mathew McLaren, Rebecca Conners, Michail N. Isupov, Patricia Gil‐Díez, Lavinia Gambelli, Vicki A. M. Gold, Andreas Walter, Sean R. Connell, Ben Williams, Bertram Daum · 发表于：Nature Microbiology · 年份：2023 · DOI：10.1038/s41564-023-01469-w · 被引用次数：34 · 研究领域：Parasitic Infections and Diagnostics、Plant and Fungal Interactions Research、RNA modifications and cancer

Translational control is an essential process for the cell to adapt to varying physiological or environmental conditions. To survive adverse conditions such as low nutrient levels, translation can be shut down almost entirely by inhibiting ribosomal function. Here we investigated eukaryotic hibernating ribosomes from the microsporidian parasite Spraguea lophii in situ by a combination of electron cryo-tomography and single-particle electron cryo-microscopy. We show that microsporidian spores contain hibernating ribosomes that are locked in a dimeric (100S) state, which is formed by a unique dimerization mechanism involving the beak region. The ribosomes within the dimer are fully assembled, suggesting that they are ready to be activated once the host cell is invaded. This study provides structural evidence for dimerization acting as a mechanism for ribosomal hibernation in microsporidia, and therefore demonstrates that eukaryotes utilize this mechanism in translational control.