Telomeres And Telomerase

Telomeres

The ends of chromosomes are capped with junk DNA called telomeres to keep the chromosomes from unravelling. Telomeres serve to protect the integrity of the chromosomes DNA that contain the genetic information of he cell.

This junk DNA is thought of as the plastic tips on the ends of shoelaces that keep them from fraying. If the chromosomes where to fray its DNA would bind with nearby chromosomes and would corrupt the cells genetic information and cell function.

Telomeres also serve to control or limit the lifespan of a cell. When cells divide the cell’s chromosomes are duplicated but the duplication process cannot copy the whole chromosome and sections at the end of the chromosome are lost during every cell division.

This duplication process results in the tips of the chromosomes becoming shorter after each cell division. If the junk DNA wasn’t present at the end of the chromosomes the DNA that contains the genetic information of the cell would be damaged after the cell division, and would result in cell death.

Since the telomeres contain DNA without any genetic information their shortening doesn’t damage their function, but when the telomeres reach a certain length the cell can longer replicate.

Telomerase

Telomerase are enzymes that are able to add junk DNA back to the end of telomeres which will extend the life of the cell. The junk DNA of telomeres are repetitive sequences of DNA.

Telomeres, which are made up of protein and RNA subunits, are able to add repetitive sequences of DNA back to the end of the chromosomes by copying its RNA into the chromosomes DNA.

The telomerase enzyme is not usually active in somatic cells, cells of the body, which is why cells of the body age and die. Telomerase is active in sperm and egg cells, and certain types of stem cells.

Studies have shown the lifestyle activities like eating a plant based diet, exercise, and stress management can increase telomerase activity and add DNA back to telomeres of somatic cells.