Abstract
Cdc2 is the cyclin-dependent kinase that controls entry of cells into mitosis. Phosphorylation of Cdc2 on threonine-14 and tyrosine-15 inhibits the activity of the enzyme and prevents premature initiation of mitosis. Although Wee1 has been identified as the kinase that phosphorylates tyrosine-15 in various organisms, the threonine-14-specific kinase has not been isolated. A complementary DNA was cloned from Xenopus that encodes Myt1, a member of the Wee1 family that was discovered to phosphorylate Cdc2 efficiently on both threonine-14 and tyrosine-15. Myt1 is a membrane-associated protein that contains a putative transmembrane segment. Immunodepletion studies suggested that Myt1 is the predominant threonine-14-specific kinase in Xenopus egg extracts. Myt1 activity is highly regulated during the cell cycle, suggesting that this relative of Wee1 plays a role in mitotic control.
Publication types
- Research Support, Non-U.S. Gov't
- Research Support, U.S. Gov't, Non-P.H.S.
- Research Support, U.S. Gov't, P.H.S.
MeSH terms
- Amino Acid Sequence
- Animals
- Base Sequence
- CDC2 Protein Kinase / metabolism*
- Cell Cycle Proteins*
- Cell Membrane / enzymology
- Cloning, Molecular
- Cyclins / metabolism
- Interphase
- Mitosis
- Molecular Sequence Data
- Mutation
- Nuclear Proteins*
- Oocytes / enzymology
- Phosphorylation
- Phosphothreonine / metabolism
- Phosphotyrosine / metabolism
- Protein Serine-Threonine Kinases / chemistry
- Protein Serine-Threonine Kinases / genetics
- Protein Serine-Threonine Kinases / metabolism*
- Protein-Tyrosine Kinases / chemistry
- Protein-Tyrosine Kinases / genetics
- Protein-Tyrosine Kinases / metabolism*
- Recombinant Proteins / metabolism
- Xenopus
- Xenopus Proteins*
Substances
- Cell Cycle Proteins
- Cyclins
- Nuclear Proteins
- Recombinant Proteins
- Xenopus Proteins
- Phosphothreonine
- Phosphotyrosine
- MYT1 kinase, Xenopus
- WEE1 protein, Xenopus
- Protein-Tyrosine Kinases
- Protein Serine-Threonine Kinases
- CDC2 Protein Kinase