Information Services banner Edinburgh Research Archive The University of Edinburgh crest

Edinburgh Research Archive >
Biological Sciences, School of >
Biological Sciences thesis and dissertation collection >

Please use this identifier to cite or link to this item: http://hdl.handle.net/1842/5729

This item has been viewed 72 times in the last year. View Statistics

Files in This Item:

File Description SizeFormat
Laing2011.zip33.02 MBMicrosoft Word
Laing2011.pdf36.35 MBAdobe PDFView/Open
Title: TLE proteins in mouse embryonic stem cell self renewal and early lineage specification
Authors: Laing, Adam
Supervisor(s): Brickman, Joshua
Burdon, Tom
Issue Date: 24-Nov-2011
Publisher: The University of Edinburgh
Abstract: TLE proteins are a closely related family of vertebrate corepressors. They have no intrinsic DNA binding ability, but are recruited as transcriptional repressors by other sequence specific proteins. TLE proteins and their homologues in other species have been implicated in many developmental processes including neurogenesis, haematopoiesis and the formation of major organs. They have also been implicated in early lineage specification in vertebrates but a direct role in this has not been found in mammals. The aim of my PhD is therefore to analyse the function of TLE proteins in early lineage specification and cell fate decisions using mouse embryonic stem cells (ESCs) as a model. The investigation of this has previously been complicated, firstly by the large array of transcription factors that TLEs interact with and secondly by redundancy between similar TLE proteins hindering loss of function approaches. To circumvent these problems, I have used two complementary experimental strategies. The first was identification of point mutations in TLE1 that affect specific classes of DNA binding. Two of these mutations L743F and R534A were of particular interest and were reversibly overexpressed in ES cells to correlate phenotypes to biochemical activity. The second strategy was the mutation of the two primary TLC genes in ES cells and early mouse embryos, TLE3 and TLE4. Complementary evidence from these approaches revealed a role for TLEs in the promotion of ES cell differentiation by repression of pluripotency/self-renewal associated genes. Additionally, neural specification was increased by TLE1 expression especially by the TLE1 point mutations, highlighting opposing roles for negative effects on mesendodermal differentiation. Early mesoderm/primitive streak was increased by loss of TLE, probably through Wnt antagonism. Anterior endoderm was increased by reduced TLE, but a critical level of TLE was still necessary and TLE1 overexpression also upregulated some anterior endoderm markers suggesting both negative and positive roles for TLE proteins in this process.
Sponsor(s): Medical Research Council (MRC)
Keywords: TLE proteins
early lineage specification
cell fate decisions
point mutations
ES cell differentiation
URI: http://hdl.handle.net/1842/5729
Appears in Collections:Biological Sciences thesis and dissertation collection

Items in ERA are protected by copyright, with all rights reserved, unless otherwise indicated.

 

Valid XHTML 1.0! Unless explicitly stated otherwise, all material is copyright © The University of Edinburgh 2013, and/or the original authors. Privacy and Cookies Policy