In Arabidopsis thaliana we have an unusual situation in that we have multiple POT proteins, where most organisms have only one. This seems to have led to a divergence of function where POT1a is associated with the Telomerase RNP and POT1b is believed to be critical for chromosome end protection. POT1c, the third member of the POT family, currently has no function ascribed to it. Studying the POT family in Arabidopsis thaliana gives us a unique opportunity to dissect the multiple functions of the POT proteins from other organisms. A knockout for POT1 in humans or Cdc13 in yeast is lethal, whereas we can knockout any one of these genes in Arabidopsis without it being lethal.