Are Mouse Telomeres Going to Pot?

Pot1 is a conserved single-stranded DNA binding protein with crucial functions in the protection of telomeres and maintenance of their length. In this issue of Cell, two papers ( Hockemeyer et al., 2006 and Wu et al., 2006) examine the roles of murine Pot1 homologs and describe intriguing new insights into how cells protect their chromosome ends from DNA-repair activities.