Blackburn wins Lasker award for telomerase research

Australian-born molecular biologist Professor Elizabeth Blackburn has won the prestigious Lasker Award for the discovery of telomerase, the enzyme that synthesises telomeres, the tiny units of DNA that seal off the ends of chromosomes.

Blackburn, 57, is the Morris Herzstein professor of biology and physiology in the Department of Biochemistry and Biophysics at the University of California, San Francisco (UCSF). She shares the award with her former postdoc student, Carol Greider, 45, of Johns Hopkins University School of Medicine and Jack Szostak, 53, of Harvard Medical School.

The Lasker Award has previously been awarded to 71 scientists who subsequently went on to receive the Nobel Prize. It has come to be known as "America's Nobels" and is the most coveted award in medical science in America.

In 1975 to 1977, as a postdoctoral fellow at Yale University, Blackburn discovered the unusual nature of telomeres. The work was published in 1978. In 1985, while a professor at University of California, Berkeley, she and Greider reported the discovery of telomerase.

Telomerase controls the ageing of our chromosomes by protecting the telomeres, simple DNA sequences that have been likened to the aglets on the ends of shoelaces. They stop the chromosomal DNA from fraying over time until eventually it cannot do its job. Average telomere length correlates with age, particularly in humans.

Telomerase, on the other hand, is the enzyme that replicates and stabilizes telomeres, thus regulating the genetic lifespan of a cell and protecting the genome for generational transfer. Telomerase is an intriguing enzyme in that it comprises an RNA component, which acts as the template for synthesis of the telomere DNA by reverse transcription, and a protein reverse transcriptase.

It is known to play a critical role in both normal cell growth and in cancer. In soon to be published work, Blackburn's research group have turned down telomerase in mouse and human melanoma cells using short interfering RNAs (siRNAs) and to their surprise, the cancers rapidly stopped growing without telomere shortening or DNA damage.

"The cool thing was that this property of the cells changed their invasiveness ... so they were happily growing and dividing ... but they could not spread," Blackburn told Australian Life Scientist recently. "Spreading of melanoma, especially to the lungs, is the thing that causes death."

Today, scientists are exploring whether the telomerase enzyme could be reactivated to prolong cell life - in order to treat age-related and neurodegenerative disorders ranging from skin wrinkles to blindness to cardiovascular disease - and deactivated to treat cancers, in which, the enzyme is usually abnormally overactive.

Broadening the scope of the research in recent years, Blackburn and UCSF colleague Elissa Epel have reported that chronic psychological stress and the perception of life stress, take a toll on telomeres and telomerase. The findings have implications for understanding how, at the cellular level, stress may promote earlier onset of age-related diseases.

The field of telomere research is made up of 50 per cent women, a statistic attributed to Blackburn's pioneering work.