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Published on: September 30, 2016
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The pseudogene RPS27AP5 expresses ubiquitin and ribosomal protein variants with potential roles in ribosome function
Anna Meller1, Jennifer Raisch1, Dominique Lévesque1
1Department of Immunology and Cell biology, Université de Sherbrooke, 3201, Jean-Mignault, Sherbrooke, QC J1E 4K8, Canada.
Biochemistry and Cell Biology = Biochimie Et Biologie Cellulaire
|September 23, 2025
Summary
Pseudogenes, once thought non-functional, can express proteins. The RPS27A pseudogene produces two variants, one of which integrates into ribosomes, impacting mRNA association and suggesting functional ribosomal diversity.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- Pseudogenes are typically considered non-functional gene relics.
- Ubiquitin is usually encoded by UBA52, RPS27A, UBB, and UBC genes.
- Evidence suggests some pseudogenes are transcribed and translated.
Purpose of the Study:
- To investigate the functional potential of the RPS27A pseudogene, RPS27AP5.
- To characterize the proteins expressed from RPS27AP5.
- To determine the impact of these proteins on cellular processes.
Main Methods:
- Affinity purification
- Polysome profiling
- Protein expression and characterization
- Ribosome analysis
Main Results:
- RPS27AP5 expresses two proteins: a ubiquitin variant (UbP5) and a ribosomal protein variant (S27aP5).
- S27aP5 integrates into 80S monosomes, and its overexpression increases this fraction.
- S27aP5-containing ribosomes show altered mRNA associations.
Conclusions:
- The RPS27A processed pseudogene can produce a functional ribosomal protein variant.
- This variant influences ribosome composition and mRNA binding.
- Ribosomes may possess functional diversity beyond canonical roles.
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