St Andrews Research Repository

St Andrews University Home
View Item 
  •   St Andrews Research Repository
  • Biology (School of)
  • Biology
  • Biology Theses
  • View Item
  •   St Andrews Research Repository
  • Biology (School of)
  • Biology
  • Biology Theses
  • View Item
  •   St Andrews Research Repository
  • Biology (School of)
  • Biology
  • Biology Theses
  • View Item
  • Login
JavaScript is disabled for your browser. Some features of this site may not work without it.

Tools for probing 2A sequence space

Thumbnail
View/Open
Helena Escuin Ordinas PhD thesis.pdf (5.785Mb)
Date
2008
Author
Escuin Ordinas, Helena
Supervisor
Ryan, Martin Denis
Metadata
Show full item record
Altmetrics Handle Statistics
Abstract
Foot-and-mouth disease virus (FMDV) 2A is an oligopeptide composed of only 18 amino acids that can mediate a co-translational cleavage at its own C- terminus. It has been observed that 2A sequences do not show cleavage activity within bacterial organisms. Why 2A lacks activity in a prokaryotic organism such as E.coli is unclear. A series of plasmids designed to provide a phenotypic screen for 2A-mediated cleavage (in prokaryotes) were developed. Even though no active 2A sequences were found in bacteria, this system can easily be adapted to eukaryotic cells and will also be very useful in mutagenic studies on 2A sequences. Furthermore, 2A[subscript(FMDV)] has been used in the construction of a reporter of stress in the cell. This may allow us to open a new approach in the use of 2A oligopeptide, which had already been widely used to co-express genes of interest with reporter proteins, in biotechnology and gene therapy. Theiler’s murine encephalomyelitis cardiovirus (TMEV) 2A has the same role as in FMDV but is 150 aa in length instead of the 18 aa in FMDV. It also presents the same C-terminal motif but what is the function of the remaining ~85% of the cardiovirus 2A sequence remains a mystery. To this end we have produced antibodies against TMEV-2A, to study the role of 2A[subscript(TMEV)] within the cell. Database searches probing for 2A’s C-terminal conserved motif (- DxExNPGP-) has identified many 2A-like sequences, not only within picornaviruses but also in trypanosomes, insect and cellular genes. These remarkable findings indicate that the control of protein synthesis by 2A is not solely confined to the Picornaviridae. Bioinformatics analyses of all the known 2A-like sequences, comparing all the different upstream sequences, show a clear pattern on the organization of residues in the upstream region. The discovery of this 2A oligopeptide has led to a breakthrough in protein co- expression technology. It has been used as a highly effective new tool for the co- expression of multiple proteins from a single ORF in plant biotechnology and also gene therapy applications. Although we have gained substantial insights into the general features and biological significance of this process, a great deal still needs to be uncovered about the structural and mechanistic details of this unique mechanism of action.
Type
Thesis, PhD Doctor of Philosophy
Collections
  • Biology Theses
URI
http://hdl.handle.net/10023/692

Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

Advanced Search

Browse

All of RepositoryCommunities & CollectionsBy Issue DateNamesTitlesSubjectsClassificationTypeFunderThis CollectionBy Issue DateNamesTitlesSubjectsClassificationTypeFunder

My Account

Login

Open Access

To find out how you can benefit from open access to research, see our library web pages and Open Access blog. For open access help contact: openaccess@st-andrews.ac.uk.

Accessibility

Read our Accessibility statement.

How to submit research papers

The full text of research papers can be submitted to the repository via Pure, the University's research information system. For help see our guide: How to deposit in Pure.

Electronic thesis deposit

Help with deposit.

Repository help

For repository help contact: Digital-Repository@st-andrews.ac.uk.

Give Feedback

Cookie policy

This site may use cookies. Please see Terms and Conditions.

Usage statistics

COUNTER-compliant statistics on downloads from the repository are available from the IRUS-UK Service. Contact us for information.

© University of St Andrews Library

University of St Andrews is a charity registered in Scotland, No SC013532.

  • Facebook
  • Twitter