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Updated: May 14, 2025
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Quantitative Methods to Study Protein Arginine Methyltransferase 1-9 Activity in Cells
Published on: August 7, 2021
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EMG1 methyltransferase activity affects ribosome occupancy at KSHV uORFs
Elena M Harrington1, James C Murphy1, Katherine L Harper1
1School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
Cell Reports
|April 11, 2025
Summary
Kaposi's sarcoma-associated herpesvirus (KSHV) hijacks host ribosomes using a specialized mechanism. The ribosomal factor EMG1 is crucial for viral protein synthesis and infectious virus production during KSHV replication.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Viruses depend on host cells for protein synthesis.
- Kaposi's sarcoma-associated herpesvirus (KSHV) uniquely alters host ribosomes for viral protein production.
- KSHV utilizes specialized ribosomes to translate viral transcripts, including those with upstream open reading frames (uORFs).
Purpose of the Study:
- To investigate the role of the ribosomal biogenesis factor EMG1 in KSHV lytic replication.
- To elucidate the mechanism by which EMG1 influences viral protein synthesis and infectious virus production.
Main Methods:
- Analysis of EMG1 association with precursor-40S ribosome complexes during KSHV infection.
- Depletion of EMG1 using genetic manipulation.
- Assessment of viral protein expression, lytic cascade progression, and infectious virus yield.
- Evaluation of EMG1's methyltransferase activity in regulating KSHV uORF translation.
Main Results:
- EMG1 shows enhanced association with precursor-40S ribosome complexes during KSHV lytic replication.
- EMG1 depletion significantly reduces viral protein expression and infectious virus production.
- The methyltransferase activity of EMG1 is essential for regulating the translation of KSHV uORFs in late lytic genes.
Conclusions:
- EMG1 plays a critical role in KSHV lytic replication by modulating host ribosome composition and function.
- EMG1-mediated regulation of viral translation is vital for efficient viral protein synthesis and infectious virion production.
- Targeting EMG1's methyltransferase activity may represent a therapeutic strategy against KSHV infection.
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