Cytoplasmic mRNA recapping has limited impact on proteome complexity
The m7G cap marks the 5′ end of all eukaryotic mRNAs, but there are also capped ends that map downstream within spliced exons. A portion of the mRNA transcriptome undergoes a cyclical process of decapping and recapping, termed cap homeostasis, which impacts the translation and stability of these mRN...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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The Royal Society
2020-11-01
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| Series: | Open Biology |
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| Online Access: | https://royalsocietypublishing.org/doi/pdf/10.1098/rsob.200313 |
| _version_ | 1828977473587511296 |
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| author | Bernice A. Agana Vicki H. Wysocki Daniel R. Schoenberg |
| author_facet | Bernice A. Agana Vicki H. Wysocki Daniel R. Schoenberg |
| author_sort | Bernice A. Agana |
| collection | DOAJ |
| description | The m7G cap marks the 5′ end of all eukaryotic mRNAs, but there are also capped ends that map downstream within spliced exons. A portion of the mRNA transcriptome undergoes a cyclical process of decapping and recapping, termed cap homeostasis, which impacts the translation and stability of these mRNAs. Blocking cytoplasmic capping results in the appearance of uncapped 5′ ends at native cap sites but also near downstream cap sites. If translation initiates at these sites the products would lack the expected N-terminal sequences, raising the possibility of a link between mRNA recapping and proteome complexity. We performed a shotgun proteomics analysis on cells carrying an inducible inhibitor of cytoplasmic capping. A total of 21 875 tryptic peptides corresponding to 3565 proteins were identified in induced and uninduced cells. Of these, only 29 proteins significantly increased, and 28 proteins significantly decreased, when cytoplasmic capping was inhibited, indicating mRNA recapping has little overall impact on protein expression. In addition, overall peptide coverage per protein did not change significantly when cytoplasmic capping was inhibited. Together with previous work, our findings indicate cap homeostasis functions primarily in gating mRNAs between translating and non-translating states, and not as a source of proteome complexity. |
| first_indexed | 2024-12-14T14:58:34Z |
| format | Article |
| id | doaj.art-8847fd0d12b346f3be4ab8eb1a6c1b5a |
| institution | Directory Open Access Journal |
| issn | 2046-2441 |
| language | English |
| last_indexed | 2024-12-14T14:58:34Z |
| publishDate | 2020-11-01 |
| publisher | The Royal Society |
| record_format | Article |
| series | Open Biology |
| spelling | doaj.art-8847fd0d12b346f3be4ab8eb1a6c1b5a2022-12-21T22:56:54ZengThe Royal SocietyOpen Biology2046-24412020-11-01101110.1098/rsob.200313200313Cytoplasmic mRNA recapping has limited impact on proteome complexityBernice A. AganaVicki H. WysockiDaniel R. SchoenbergThe m7G cap marks the 5′ end of all eukaryotic mRNAs, but there are also capped ends that map downstream within spliced exons. A portion of the mRNA transcriptome undergoes a cyclical process of decapping and recapping, termed cap homeostasis, which impacts the translation and stability of these mRNAs. Blocking cytoplasmic capping results in the appearance of uncapped 5′ ends at native cap sites but also near downstream cap sites. If translation initiates at these sites the products would lack the expected N-terminal sequences, raising the possibility of a link between mRNA recapping and proteome complexity. We performed a shotgun proteomics analysis on cells carrying an inducible inhibitor of cytoplasmic capping. A total of 21 875 tryptic peptides corresponding to 3565 proteins were identified in induced and uninduced cells. Of these, only 29 proteins significantly increased, and 28 proteins significantly decreased, when cytoplasmic capping was inhibited, indicating mRNA recapping has little overall impact on protein expression. In addition, overall peptide coverage per protein did not change significantly when cytoplasmic capping was inhibited. Together with previous work, our findings indicate cap homeostasis functions primarily in gating mRNAs between translating and non-translating states, and not as a source of proteome complexity.https://royalsocietypublishing.org/doi/pdf/10.1098/rsob.200313rna processingproteomicstranslationprotein expressionmrna capcytoplasmic capping |
| spellingShingle | Bernice A. Agana Vicki H. Wysocki Daniel R. Schoenberg Cytoplasmic mRNA recapping has limited impact on proteome complexity Open Biology rna processing proteomics translation protein expression mrna cap cytoplasmic capping |
| title | Cytoplasmic mRNA recapping has limited impact on proteome complexity |
| title_full | Cytoplasmic mRNA recapping has limited impact on proteome complexity |
| title_fullStr | Cytoplasmic mRNA recapping has limited impact on proteome complexity |
| title_full_unstemmed | Cytoplasmic mRNA recapping has limited impact on proteome complexity |
| title_short | Cytoplasmic mRNA recapping has limited impact on proteome complexity |
| title_sort | cytoplasmic mrna recapping has limited impact on proteome complexity |
| topic | rna processing proteomics translation protein expression mrna cap cytoplasmic capping |
| url | https://royalsocietypublishing.org/doi/pdf/10.1098/rsob.200313 |
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