In the field of “Regulation of MGMT” the research group of Prof. Dr. Bernd Kaina offers the following PhD project:
Regulation of MGMT: Impact on genomic stability
Description:
In this proposal, we wish to address the following questions:
1) Is the MGMT promoter in human cells subject to upregulation by genotoxic stress (ionizing radiation, MNNG, temozolomide, CCNU)?
2) Does upregulation depend on the MGMT status of the cells? We have cloned the full-length MGMT promoter in a luciferase construct, which is ready for transient transfection experiments. Our background data show that the promoter is highly active and can be expressed in MGMT + and MGMT – cells, indicating that cellular MGMT promoter methylation has no impact on the expression of the transfected promoter. Next we wish to determine the expression of the promoter in brain tumor cells and human liver cells that express low and high MGMT, respectively. This work is aimed at identifying transcription factors that are responsible for MGMT regulation in these tissues.
3) Is MGMT in human cells regulated by glucocorticoids? This is an important question since glucocorticoids are used in tumor chemotherapy. Moreover, they are stress hormones and could have impact on the general genotoxic defense in humans. The MGMT promoter harbours two GREs. We wish to explore the promoter activity in cells with and without glucocorticoid receptor, and in the presence and absence of dexamethasone. Glucocorticoid responsiveness will be confirmed by mutational inactivation of GREs.
4) Is MGMT subject to regulation by BRCA2? Following a recent report (11) describing that BRCA2 is degraded by the inactive MGMT and also by O6BG, we wish to elucidate this finding for relevance to DNA breakage and drug resistance of glioma and melanoma cells. BRCA2 levels will be measured in MGMT + and MGMT – tumor cells in vitro and related to the MGMT repair level and HR. Further the genotoxicity will be determined.
5) Are there natural compounds that stimulate MGMT expression? Taking advantage of our reporter construct, we will screen a natural compound library to identify potential regulators of this repair gene. It is obvious that this work has strong impact on identifying beneficial, anticancer natural products. At the same time we will be able to identify suppressors of MGMT. Thus, we are interested in elucidating whether upregulation of 5-MeC-DNA-methyltransferase following genotoxic stress is able to silence MGMT and, vice versa, upregulation of GADD45 has an impact on its downregulation.
6) Having found that MGMT is induced in human cells following non-genotoxic or genotoxic stress, the question arises whether under the induced conditions MGMT causes a threshold for the mutagenic and the toxic affects of alkylating agents. We will also include MGMT ko mice lacking MGMT to determine whether MGMT causes a threshold in colon cancer formation.
We offer:
• The possibility to work on a cutting-edge project using state-of-the-art technology in a highly motivated research team
• A stimulating, diverse and international research environment
• Advanced training opportunities
• A competitive stipend
Required qualifications:
• Master or Diploma
• Motivation to solve complex biological problems
• Excellent communication skills
Starting date: 1 March 2014 or later
Duration of stipend: 3 years, with the possibility of extension
Deadline for applications (exclusively online via web form): 25 November 2013
Job details
Employer:Institute of Molecular Biology (IMB) Mainz
Website:http://www.imb.de/PhD
Location:Institut für Molekulare Biologie gGmbH, Ackermannweg 4, 55128 Mainz, Rhineland-Palatinate, Germany
Expires:November 25, 2013
Job type:PhD Studentship
Qualifications:Postgraduate - Master's degree
Employment type:Contract
Job hours:Full-time