The aims of this thesis were to determine the relative contribution of Pdx-1, MafA and β2 to the human insulin promoter. Additionally, characterisation of the conserved CRE element (CRE2) was undertaken to identify the factor(s) that bind CRE2 to mediate affects upon the transcription of insulin. Finally, the ectopic expression of insulin was investigated using an engineered zinc finger protein (ZFP-INS) that ‘switched on’ the endogenous insulin gene in a non-β cell (HEK293). Consistent with previous findings, Pdx-1, MafA and β2 were shown to synergistically activate the rat insulin 1 promoter. However due to subtle sequence divergence, similar synergistic interaction was not observed on the human promoter. Synergistic interactions were re-established in a rat insulin 1-like mutated human insulin construct. The CRE binding protein activating transcription factor-2 (ATF-2) was shown to bind and stimulate transcription via CRE2 while CRE binding protein-1 (CREB-1) inhibited insulin transcription independently of CRE1 or CRE2. ZFP-INS was shown to induce the ectopic expression of insulin in HEK293 cells via the ILPR region, inducing modifications of histone proteins at the insulin promoter. Collectively, the continued characterisation of the human insulin promoter may reveal unique regulatory mechanisms controlling the expression of insulin under normal and diabetic conditions.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:499108 |
| Date | January 2008 |
| Creators | Ferguson, Laura A. |
| Publisher | University of Aberdeen |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=25965 |
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