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

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.

Level dc:type.qualificationlevel

PhD

Grantor dc:publisher.institution

University of Glasgow

Year dc:date.issued

2009

Author dc:creator

• Strogantsev, Ruslan S.

• R Medicine (General)
• Q Science (General)

DOI dc:identifier.doi

https://doi.org/10.5525/gla.thesis.1195

OAI identifier oai:identifier

oai:theses.gla.ac.uk:1195