Visualizing the Telomerase Molecular Motor Extend the Ends of DNA

We will study the elementary kinetics of the molecular motor telomerase[1]. In the absence of this molecular motor, the chromosomes in our cells are truncated with every cellular division, which ultimately leads to cell death. Using an internal template as a blueprint, telomerase adds nucleotides to the ends of chromosomes, reversing their otherwise inevitable shortening. This activity of telomerase has been correlated to cell immortality[2, 3]. Despite extensive biochemical research, many fundamental questions regarding the mechanism of telomerase remain unanswered. To a large extent, this can be attributed to the difficulty of studying the kinetics of this molecular motor in bulk experiments. Without knowledge of the dynamics of this molecular motor, it is difficult to gauge the interplay between its protein and RNA components. Likewise, the kinetics of nucleotide incorporation and processivity are unknown. Since telomerase is particularly highly expressed in ?immortal? cells, i.e. cancer cells, a fundamental understanding of its mechanism is critical to the development of more effective drugs. Furthermore, the mechanism of telomerase has important implications for the fundamental cellular process of aging. We will address the mechanics of this molecular motor using both highly-precise biophysical techniques (single-molecule fluorescence microscopy and microfabrication) and state-of-the-art biochemistry. Single-molecule techniques, which can address questions inaccessible in bulk experiments, have not previously been applied to telomerases. We are in the fortunate position of collaborating with the group that discovered the enzyme telomerase and remains a leader in the field, the group of Prof. E. Blackburn of the University of California, San Francisco. Both the purification of this enzyme and the incorporation of mutations will be carried out by this world-class group. Our integrated approach provides a great opportunity for resolving the underlying mechanism of this enzyme, provided that CW funding can be obtained.