Study of G-quadruplex formation in the promoter region of zinc transporter hZIP1
File(s)
Author(s)
Franco Bodek, Daniela
Type
Thesis
Abstract
The formation of G-quadruplexes, non-canonical DNA structures, in the promoter region of genes has attracted a lot of attention in recent years as regulators of gene expression; these structures have become attractive targets for therapeutic design of molecules. In this thesis, the effect of a putative G-quadruplex sequence was investigated in the promoter region of hZIP1, an important zinc transporter that is down-regulated during the development of prostate cancer. Understanding the mechanisms of regulation of this gene is fundamental to unravel the processes that govern the malignancy progress. It was found that the G-rich sequence (named hZIP1-1) located near the transcription start site of hZIP1 is capable of forming stable parallel intramolecular G-quadruplexes at physiological pH and potassium concentration in vitro. Mutations that disrupt the G-quadruplex potential were designed with emphasis on preventing the disruption of known and predicted transcription binding sites. The well-studied G-quadruplex ligands Pyridostatin, BRACO-19 and PhenDC3 were found to stabilize the G-quadruplex sequence while having little effect on the non-G-quadruplex mutant. In cellulo studies revealed that disrupting the G-quadruplex potential of the hZIP1 promoter decreases transcription. Furthermore, treatment with Pyridostatin increases transcription. These results suggest that the G-quadruplex may function as an activator of gene expression that can be targeted using G-quadruplex selective small molecules, providing a new therapeutic route to be explored in the treatment of prostate cancer.
Version
Open Access
Date Issued
2016-02
Date Awarded
2016-09
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Vilar, Ramon
Woscholski, Rudiger
Sponsor
Consejo Nacional de Ciencia y Tecnología
Publisher Department
Chemistry
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)