Cdc14 family phosphatases are highly conserved regulators of cell-cycle progression. Regulated release from the nucleolus partly controls the activity of budding yeast Cdc14p and its fission yeast ortholog Clp1/Flp1. But here, report Dannel McCollum and colleagues, the similarities stop (see p. 4462). In budding yeast, a network of FEAR (for Cdc-fourteen early anaphase release) proteins triggers the release of Cdc14p from the nucleolus in early anaphase. When McCollum and co-authors examine fission yeast mutants lacking FEAR protein orthologs, however, they find that release of Clp1/Flp1 from the nucleolus, which normally occurs upon entry into mitosis in this organism, is unaffected, which indicates that is not triggered by the FEAR network. In addition, they show that, whereas Cdc14p promotes the segregation of nucleolar and telomeric DNA, Clp1p/Flp1 is not required for these processes. Thus, although Cdc14 family phosphatases themselves are highly conserved, their regulation and functions may not be universal. In particular, suggest the authors, several Cdc14 orthologs – including the human form – might be regulated through a conserved FEAR-independent pathway.
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