Research objectives and content:
Research objectives: The aim of the research proposal is to elucidate the role of Chk1p in the function of DNA structure checkpoints. Understanding of those is of considerable importance and may help to provide more effective means for cancer treatment.
Content: Cells must delay progression through the cell cycle in response to DNA damage. This is achieved by the action of DNA structure checkpoint mechanisms that arrest cell division in case of a problem. A human gene, ATM, implicated in DNA structure checkpoints has recently been cloned. Mutations in this gene cause Ataxia-Telangiectasia, a disease manifested by pleiotropic effects, among others a drastic increase in radiation sensitivity and the frequency of tumour development. Although the disease is recessive and relatively rare, heterozygotes, also have an increased cancer risk. A homologue of the ATM gene also exist in S.pombe (rad3). The S.pombe chkl gene product to be investigated under this proposal acts downstream of rad3. Its function is to be examined with the following approaches.
? Identification of suppressers (i.e. downstream effectors) of chkl ? Identification of effectors of the rad3- Chkl pathway: I.e. to find elements involved in mediating the cell cycle arrest in response to DNA damage
? Characterisation of the human homologue: Verification of results obtained in the genetic screen and extension in mammalian cells. Training content (objective, benefit and expected impact)
objective: To gain experience in the use of yeast genetics and to further my understanding of checkpoint mechanisms in particular of DNA structure checkpoints and their interaction with the cell cycle.
benefit: My PhD studies provided me with experience in cell biology and biochemistry in cell cycle research in a marnmalian system. The possibility to expand my experience to the use of yeast genetics will allow the analysis of pathways and dependencies, and allow to bring genetic analysis and biochemical methods together.
impact: The combined use of Genetics and Biochemistry will allow the full exploitation of the respective advantages of both these techniques in addressing fundamental biological problems now and in the future whose analysis would be limited if analysed only by one of the approaches Links with industry / industrial relevance (22)
A collaboration with industry exists in the host laboratory over a project related to this proposal. Two posts and a consultancy between the lab head and the company are funded. This collaboration implements a drug discovery program based on a high throughput screening, involving the rad3 and ATR (human homologue) proteins. (The activity of these is required for the phosphorylation of chkl.) Depending on the outcome of the proposed research project it is likely, that interest in the exploitation of chk1p as a potential target for drugs will arise, as already indicated by the industrial contributions to a project aimed at making a chk1 knockout mouse.