Telomerase: a scarce enzyme
Although telomerase is present in the majority of cancers, the amount of telomerase within a cancer cell is extremely low (<100 molecules). Thus, over-expression of telomerase is necessary for many of the assays we perform and the goals we aim to achieve. In collaboration with Dr. Scott Cohen at CMRI, and Drs George Lovrecz and Tim Adams at the CSIRO (Parkville), we have established a telomerase over-expression and purification system wherein the three components of the enzyme complex (hTERT, hTR, and the RNA binding protein dyskerin) are over-expressed in human cells, and the enzyme then purified using our established procedure, including an in-house antibody that effectively immunoprecipitates the enzyme. Currently our system yields ~1,000-fold over-expression and is carried out on the 20-L bioreactor scale; in a constant effort to get more enzyme, this continues to be an active area of research.