Greider gives WISMAC lecture

By Amanda Siegfried 

Dr. Carol Greider, a pioneer in research on the structure of telomeres and the function of the enzyme telomerase, spoke to a full auditorium on campus Feb. 4 as the Ida M. Green Distinguished Visiting Professor Honoring Women in Science and Medicine.

Dr. Greider’s lecture, titled “Telomerase and the Consequences of Telomere Dysfunction,” was presented in the Excellence in Education Foundation Auditorium in the Simmons /Hamon Biomedical Research buildings.

Dr. Carol Greider

Each year UT Southwestern's Women in Science and Medicine Advisory Committee (WISMAC) selects and hosts a distinguished female scientist/physician who visits campus for a two-day professorship that includes meetings with individuals and campus groups and a university lecture. 

A member of the National Academy of Sciences, Dr. Greider is director of the department of molecular biology and genetics at Johns Hopkins University School of Medicine. Dr. Greider received the 2006 Albert Lasker Award for Basic Medical Research along with Dr. Elizabeth Blackburn of the University of California, San Francisco, and Dr. Jack Szostak of Harvard Medical School.

Functional elements

Telomeres are functional elements on the ends of chromosomes. Each time a cell divides, telomeres shorten a bit, and once the telomeres reach a certain diminished length, the cell stops dividing. The mechanism normally limits cells to a fixed life span, but when it goes awry, unchecked growth and cancer can develop.

In 1984 Dr. Greider was working as a graduate student in the laboratory of Dr. Blackburn at UC Berkeley when they discovered the enzyme telomerase, which maintains the length of telomeres. When present, telomerase can allow cells to continue to divide indefinitely, essentially making them immortal. Many cancer cells express telomerase.

During her campus lecture, Dr. Greider said that although increased function of telomerase is implicated in cancer, it is also necessary in cells that must continue to divide for many generations, such as stem cells.

She also described a human disease, dyskeratosis congenita, in which patients exhibit symptoms that include skin and nail disorders, bone marrow dysfunction, premature aging and increased risk of cancer. Dysfunction of the telomere/telomerase system could be to blame, she said.

“This is a very finely balanced system,” she said. “Many phenotypes from telomere-shortening syndromes resemble age-related diseases.” Such conditions include bone marrow failure, osteoporosis, immune deficiency and lung disease.

Dr. Greider said it may someday be possible to treat and repair telomerase malfunctions in a patient’s bone marrow outside of the body, then transplant the marrow back, with no danger of rejection.

“Dr. Greider’s research has provided important insights into the processes of cancer and aging,” said Dr. Susanne Mumby, assistant dean for postdoctoral affairs at UT Southwestern and co-chair of WISMAC. “She and her colleagues utilize biochemistry, yeast and mice to explore how telomeres function to provide chromosome stability and how telomerase contributes to the viability of cancer and stem cells.”

Academic achievements

Dr. Greider received her Ph.D. in molecular biology from UC Berkeley. She completed her postdoctoral studies at Cold Spring Harbor Laboratory, where she later became an in­vestigator, and she joined the Johns Hopkins faculty in 1997.

WISMAC is an institutional committee composed of appointed representatives of the faculty, staff, fellows and the student body.  Its goal is to promote representation and recog­nition for women in all campus activities and to provide inspiration to junior faculty and trainees.

Southwestern Medical Foundation sponsors the distinguished visiting professorship, established in honor of Ida Green, the wife of Texas Instruments founder Cecil H. Green.

Mrs. Green, who died in 1986, was a great supporter of opening career paths for women in science and medicine and provided a major bequest to Southwestern Medical Foundation. Mr. Green died in 2003.