Mapping and characterisation of genomic binding sites of the chromatin barrier protein VEZF1

Strogantsev, Ruslan S. (2009) Mapping and characterisation of genomic binding sites of the chromatin barrier protein VEZF1. PhD thesis, University of Glasgow.

Abstract

VEZF1 is a highly conserved transcription factor that is restricted to vertebrates. A chicken homologue of this protein, BGP1 has been recently identified to function at the HS4 insulator element demarcating the 5' boundary of the chicken β-globin domain. BGP1 binding sites are required for chromatin barrier activity and are associated with protection from de novo DNA methylation. Gene targeting experiments in mice have also revealed crucial roles for Vezf1 in vascular and lymphatic development.
Work described in my thesis utilises a ChIP-chip approach to map VEZF1 binding sites across 1% of the human genome, known as the ENCODE regions, in K562 erythroid cells. It was found that VEZF1 preferentially targets gene regulatory elements and promoters of actively transcribed genes in particular. A significant proportion of intergenic sites were identified at the boundary regions between active and repressive chromatin. This indicates that these may harbour insulator activities akin to HS4. In addition, a subset of binding sites were found to bind VEZF1 in tissue specific manner being restricted to haemopoietic/ erythroid lineages. Depletion of VEZF1 levels in K562 cells results in specific downregulation of alpha- and beta-globin gene RNA levels, whilst expression of more than 20 other gene targets bound by VEZF1 remains unchanged.
Findings presented in this thesis provide a global view of VEZF1 mediated functions in the genome and highlight its potential roles in regulating endothelial and haemopoietic gene expression.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Due to copyright restrictions the full text of this thesis cannot be made available online. Access to the printed version is available
• Keywords: VEZF1, transcription factor, ChIP-chip, chromatin, insulators, barrier elements, gene expression
• Subjects: R Medicine > R Medicine (General); Q Science > Q Science (General)
• Colleges/Schools: College of Medical Veterinary and Life Sciences > School of Cancer Sciences
• Supervisor's Name: West, Dr Adam
• Date of Award: 2009
• Depositing User: Mr Ruslan/ RS Strogantsev
• Unique ID: glathesis:2009-1195
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 06 Oct 2009
• Last Modified: 10 Dec 2012 13:35
• URI: https://theses.gla.ac.uk/id/eprint/1195