Scientists have long known that DNA segments called telomeres play a crucial part in our aging process, but new research has discovered a protein that acts as a kind of cellular timekeeper, regulating the length of telomeres to maintain healthy cell division and prevent the development of cancer.
Telomeres are little caps made of repetitive sections of DNA at the end of each chromosome, and whenever a cell divides they take the hit. “Telomeres represent the clock of a cell,” says Eros Lazzerini Denchi, corresponding author of the study.
“You are born with telomeres of a certain length, and every time a cell divides, it loses a little bit of the telomere. Once the telomere is too short, the cell cannot divide anymore.”
Back in 2010, a Harvard study was able to slow and even reverse the aging process in mice by manipulating telomerase, an enzyme that helps replenish telomeres.
Until recently, scientists thought they knew of all proteins that bind to telomeres: namely telomerase and Shelterin, a protein complex that helps protect telomeres and regulate telomerase.
Now scientists from the Scripps Research Institute have discovered a new protein, called TZAP. TZAP’s role is to control a process called telomere trimming, which keeps the telomeres within that sweet spot of proliferation: long enough to be healthy, but below the risky upper limit.