Abstract
Growing evidence suggests that ribosomes selectively regulate translation of specific mRNA subsets. Here, quantitative proteomics and cryoelectron microscopy demonstrate that poxvirus infection does not alter ribosomal subunit protein (RP) composition but skews 40S rotation states and displaces the 40S head domain. Genetic knockout screens employing metabolic assays and a dual-reporter virus further identified two RPs that selectively regulate non-canonical translation of late poxvirus mRNAs, which contain unusual 5′ poly(A) leaders: receptor of activated C kinase 1 (RACK1) and RPLP2. RACK1 is a component of the altered 40S head domain, while RPLP2 is a subunit of the P-stalk, wherein RPLP0 anchors two heterodimers of RPLP1 and RPLP2 to the large 60S subunit. RPLP0 was required for global translation, yet RPLP1 was dispensable, while RPLP2 was specifically required for non-canonical poxvirus protein synthesis. From these combined results, we demonstrate that poxviruses structurally customize ribosomes and become reliant upon traditionally non-essential RPs from both ribosomal subunits for efficient initiation on their late mRNAs.
| Original language | English (US) |
|---|---|
| Article number | 115119 |
| Journal | Cell reports |
| Volume | 44 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 28 2025 |
Funding
We thank John Connor, Bernard Moss, Ian Mohr, Jingxin Cao, and Yan Xiang for kindly providing reagents. We also thank the University of Utah Beckman Center for cryo-EM imaging and the Center for High Performance Computing for computational support. This work was supported by funding from the National Institutes of Health , grant nos. R01AI165236 and R21AI174864 to J.F.H., S10OD032464-01A1 to J.N.S., R35GM133772 to P.S.S., and R01AI127456 to P.S.S. and D.W.
Keywords
- CP: Molecular biology
- CRISPR screen
- P-stalk
- RACK1
- RPLP2
- cryo-EM
- poxvirus
- ribosome customization
- translational control
ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology