White Rose University Consortium logo
University of Leeds logo University of Sheffield logo York University logo

Over-expression of DNA methyltransferase MET1 in Arabidopsis creates novel epi-alleles with heritable expression state

Brocklehurst, Samuel George Philip (2017) Over-expression of DNA methyltransferase MET1 in Arabidopsis creates novel epi-alleles with heritable expression state. PhD thesis, University of Leeds.

[img] Text
Brocklehurst_SGP_School of Biology_PhD_2017.pdf - Final eThesis - complete (pdf)
Restricted until 1 February 2023.

Request a copy

Abstract

DNA methylation marks and histone modifications are important factors involved in regulating gene expression and genome structure. By destabilizing these vital factors we can create novel epi-alleles that are transgenerational. To investigate the potential of destabilizing an epigenetic function, we over-expressed DNA METHYLTRANSFERASE1 (MET1) in both Arabidopsis and tomato. In Arabidopsis thaliana, MET1 controls maintenance of cytosine methylation at symmetrical CG positions. At certain densely methylated loci, loss of MET1 causes the loss of all cytosine methylation marks. Over-expression of either the catalytically active or inactive versions of MET1 in Arabidopsis stochastically generates new epi-alleles at loci encoding transposable elements, non-coding RNAs, and proteins, which mainly results in increased expression. These altered expression states can be transmitted to the next generation, without the need for increased MET1 concentration, but long-term stability differs for individual loci. Destabilizing epigenetic factors in tomato appears to be more sensitive, causing lethality when levels of MET1 are increased at certain stages of development. The over-expression of MET1, or other epigenetic factors, offers an alternative strategy to create novel epi-alleles, identify phenotypes under epigenetic control and determine which genes are epigenetically regulated.

Item Type: Thesis (PhD)
Academic Units: The University of Leeds > Faculty of Biological Sciences (Leeds) > School of Biology (Leeds)
Depositing User: Mr Samuel G P Brocklehurst
Date Deposited: 24 Jan 2018 12:13
Last Modified: 24 Jan 2018 12:13
URI: http://etheses.whiterose.ac.uk/id/eprint/19119

Please use the 'Request a copy' link(s) above to request this thesis. This will be sent directly to someone who may authorise access.
You can contact us about this thesis. If you need to make a general enquiry, please see the Contact us page.

Actions (repository staff only: login required)