Download MendeleyNucleolar maturation of the human small subunit processome.
Singh, S., Vanden Broeck, A., Miller, L., Chaker-Margot, M., Klinge, S.(2021) Science 373: eabj5338-eabj5338
- PubMed: 34516797
- DOI: https://doi.org/10.1126/science.abj5338
- Primary Citation of Related Structures:
7MQ8, 7MQ9, 7MQA, 7MQJ - PubMed Abstract:
The human small subunit processome mediates early maturation of the small ribosomal subunit by coupling RNA folding to subsequent RNA cleavage and processing steps. We report the high-resolution cryo–electron microscopy structures of maturing human small subunit (SSU) processomes at resolutions of 2.7 to 3.9 angstroms. These structures reveal the molecular mechanisms that enable crucial progressions during SSU processome maturation. RNA folding states within these particles are communicated to and coordinated with key enzymes that drive irreversible steps such as targeted exosome-mediated RNA degradation, protein-guided site-specific endonucleolytic RNA cleavage, and tightly controlled RNA unwinding. These conserved mechanisms highlight the SSU processome’s impressive structural plasticity, which endows this 4.5-megadalton nucleolar assembly with the distinctive ability to mature the small ribosomal subunit from within.
Organizational Affiliation:
Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, NY 10065, USA.
