Telomerase

Targets for Cancer Treatment

The ends of chromosomes

• DNA polymerase has trouble copying the tips of chromosomes- so why don’t we loose a little bit of information each time the cell replicates?

Telomeres- the ends of shoe laces

http://www.indiamart.com/srivaishnavi/shoes-laces-cords-and-tapes.html

http://en.wikipedia.org/wiki/File:Telomere_caps.gif

DNA cap

• The DNA that is lost each time is “useless” DNA- it is just repeating meaningless bases

• The length of this region keeps track of how old the cell is

• Once the telomere gets too short the cell is programmed- it knows- to die

Hayflick Limit

• A cell can only divide so many times before it dies

• In the lab we keep track of how many plates the cells have filled- we know when they’re getting old

• People had observed this and didn’t know why it happened

Telomerase

• Telomerase adds telomeres to the ends of chromosomes- keeping a cell line alive longer– A cell line is a family of cells that all came from a

single parent cell

• Some people have speculated that it could turn back aging- why?

Cancer and telomerase

• What will be different about telomerase in cancer cells?