Understanding the role of eIF4A in gene regulation in health and disease
Eukaryotic initiation factor 4A (eIF4A) is an ATP-dependent RNA helicase responsible for unwinding the secondary structure of mRNAs. In humans, eIF4A exists as three separate paralogs: eIF4AI and eIF4AII possess a high degree of homology while eIF4AIII is distinct. Knockdown of eIF4AII had no effect...
| Main Author: | |
|---|---|
| Format: | Thesis (University of Nottingham only) |
| Language: | English |
| Published: |
2012
|
| Subjects: | |
| Online Access: | https://eprints.nottingham.ac.uk/12724/ |
| _version_ | 1848791568116350976 |
|---|---|
| author | Webb, Thomas E. |
| author_facet | Webb, Thomas E. |
| author_sort | Webb, Thomas E. |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | Eukaryotic initiation factor 4A (eIF4A) is an ATP-dependent RNA helicase responsible for unwinding the secondary structure of mRNAs. In humans, eIF4A exists as three separate paralogs: eIF4AI and eIF4AII possess a high degree of homology while eIF4AIII is distinct. Knockdown of eIF4AII had no effect on the expression of a reporter construct containing a structured RNA hairpin. Knockdown of eIF4AI and treatment with hippuristanol (an eIF4A inhibitor) caused a dramatic reduction in the hairpin-mediated gene. This reporter system was developed as part of this project to act as a screen for eIF4A activity along with an in vitro screening approach.
The activity of eIF4A is suppressed in vivo by the tumour suppressor PDCD4. The fact that loss of PDCD4 function increases the severity of DNA damage is probably attributable its eIF4A-suppressive activity.
Based on previous microarray data, it was supposed that eIF4A inhibition may be therapeutically beneficial in the treatment of Alzheimer's disease. As part of this project, it was demonstrated that eIF4A suppression significantly reduced the expression of reporter genes preceded by the 5’ UTRs of genes predicted to play harmful roles in Alzheimer’s disease. The expression of reporter genes preceded by the 5’ UTR sequences of genes predicted to be beneficial in Alzheimer's were not affected by this suppression.
Reporter plasmids containing the 5’ UTR sequences of the oncogenes ODC1, EGFR and VEGFA have high requirements for eIF4A as estimated using hippuristanol. eIF4A inhibition did not significantly affect the reporters containing the 5’ UTRs of non-pathogenic genes. The EGFR 5’ UTR was found to contain an IRES which explains why EGFR is upregulated in response to hypoxia. |
| first_indexed | 2025-11-14T18:30:34Z |
| format | Thesis (University of Nottingham only) |
| id | nottingham-12724 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T18:30:34Z |
| publishDate | 2012 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-127242025-02-28T11:21:01Z https://eprints.nottingham.ac.uk/12724/ Understanding the role of eIF4A in gene regulation in health and disease Webb, Thomas E. Eukaryotic initiation factor 4A (eIF4A) is an ATP-dependent RNA helicase responsible for unwinding the secondary structure of mRNAs. In humans, eIF4A exists as three separate paralogs: eIF4AI and eIF4AII possess a high degree of homology while eIF4AIII is distinct. Knockdown of eIF4AII had no effect on the expression of a reporter construct containing a structured RNA hairpin. Knockdown of eIF4AI and treatment with hippuristanol (an eIF4A inhibitor) caused a dramatic reduction in the hairpin-mediated gene. This reporter system was developed as part of this project to act as a screen for eIF4A activity along with an in vitro screening approach. The activity of eIF4A is suppressed in vivo by the tumour suppressor PDCD4. The fact that loss of PDCD4 function increases the severity of DNA damage is probably attributable its eIF4A-suppressive activity. Based on previous microarray data, it was supposed that eIF4A inhibition may be therapeutically beneficial in the treatment of Alzheimer's disease. As part of this project, it was demonstrated that eIF4A suppression significantly reduced the expression of reporter genes preceded by the 5’ UTRs of genes predicted to play harmful roles in Alzheimer’s disease. The expression of reporter genes preceded by the 5’ UTR sequences of genes predicted to be beneficial in Alzheimer's were not affected by this suppression. Reporter plasmids containing the 5’ UTR sequences of the oncogenes ODC1, EGFR and VEGFA have high requirements for eIF4A as estimated using hippuristanol. eIF4A inhibition did not significantly affect the reporters containing the 5’ UTRs of non-pathogenic genes. The EGFR 5’ UTR was found to contain an IRES which explains why EGFR is upregulated in response to hypoxia. 2012-12-13 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en arr https://eprints.nottingham.ac.uk/12724/1/Understanding_the_Role_of_eIF4A_in_Gene_Regulation_in_Health_and_Disease_Thomas_Webb_PhD_Thesis.pdf Webb, Thomas E. (2012) Understanding the role of eIF4A in gene regulation in health and disease. PhD thesis, University of Nottingham. eIF4A EGFR Alzheimer's Cancer |
| spellingShingle | eIF4A EGFR Alzheimer's Cancer Webb, Thomas E. Understanding the role of eIF4A in gene regulation in health and disease |
| title | Understanding the role of eIF4A in gene regulation in health and disease |
| title_full | Understanding the role of eIF4A in gene regulation in health and disease |
| title_fullStr | Understanding the role of eIF4A in gene regulation in health and disease |
| title_full_unstemmed | Understanding the role of eIF4A in gene regulation in health and disease |
| title_short | Understanding the role of eIF4A in gene regulation in health and disease |
| title_sort | understanding the role of eif4a in gene regulation in health and disease |
| topic | eIF4A EGFR Alzheimer's Cancer |
| url | https://eprints.nottingham.ac.uk/12724/ |