Send to

Choose Destination
See comment in PubMed Commons below
Science. 1990 Dec 14;250(4987):1573-6.

Complementation of the mitotic activator, p80cdc25, by a human protein-tyrosine phosphatase.

Author information

  • 1Department of Biochemistry, University of Oxford, United Kingdom.


The onset of M phase requires the activation of the pp34 protein kinase in all eukaryotes thus far examined. In Schizosaccharomyces pombe, pp34 is phosphorylated on Tyr15, and dephosphorylation of this residue regulates the initiation of mitosis. In this study, it is shown that dephosphorylation of Tyr15 triggered activation of the pp34-cyclin complex from fission yeast, that a human protein-tyrosine phosphatase can catalyze this event both in vitro and in vivo, and that activation of fission yeast pp34 does not require threonine dephosphorylation. The complementary DNA that encoded the tyrosine phosphatase replaced the mitotic activator p80cdc25, closely associating the cdc25(+)-activating pathway with tyrosine dephosphorylation of pp34.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Support Center