title: Ubiquitin, SUMO, and phosphate: how a trio of posttranslational modifiers governs protein fate.
abstract: In this issue of Molecular Cell, Guo et al. (2012) demonstrate how a series of sequential posttranslational modifications, phosphorylation, sumoylation, and ubiquitylation, cooperate to target human flap endonuclease FEN1 to degradation by the proteasome at the end of S phase.
authors.affiliation: Cancer Research UK London Research Institute, Clare Hall Laboratories, Blanche Lane, South Mimms EN6 3LD, UK. helle.ulrich@cancer.org.uk
authors.forename: Helle D
authors.initials: HD
authors.lastname: Ulrich