CLICK HERE FOR A HIGH RESOLUTION IMAGE. A. Phosphorylation of the heterochromatin protein HP1 at sites of DNA damage (see Ayoub et al Nature (2008)). B. Transient mobilization of HP1 followed by accumulation at sites of DNA damage controls early events in DNA damage signaling (see Venkitaraman et al Crit Rev Biochem Mol Biol (2010)). C. Exploiting the N-end rule to construct a thermosensitive protein ‘degron’ as a general tool for conditional genetics in vertebrate cells. The right-hand panel shows the depletion and restitution of an an EGFP-degron with temperature shifts (see Su et al Nature Str Mol Biol (2008) and Bernal et al J Cell Biol (2011)).