Open AccessA role for cAMP-dependent protein kinase in early embryonic divisions.
Author(s) -
Domenico Grieco,
Enrico V. Avvedimento,
Max E. Gottesman
Publication year - 1994
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.91.21.9896
Subject(s) - cdc25 , maturation promoting factor , interphase , mitosis , protein kinase a , microbiology and biotechnology , biology , cell cycle , protein phosphatase 2 , okadaic acid , protein tyrosine phosphatase , cyclin dependent kinase 1 , phosphatase , kinase , chemistry , phosphorylation , biochemistry , cell
The cAMP-dependent protein kinase (PKA) pathway affects cell cycle progression in "cycling" Xenopus egg extracts. The concentration of free PKA catalytic subunit oscillates during the cell cycle with a peak at the mitosis-interphase transition and a minimum at the onset of mitosis. Inhibition of endogenous PKA in interphase hastens the onset of mitosis. Stimulation of PKA induces interphase arrest, preventing the activation of the M-phase-promoting factor. PKA does not block the accumulation of cyclin or its binding to p34cdc2, but the resultant complex lacks kinase activity and p34cdc2 remains tyrosine-phosphorylated. PKA appears to stimulate an okadaic acid-sensitive serine/threonine phosphatase that acts upon cdc25. In this way PKA could downregulate the p34cdc2 tyrosine phosphatase activity of cdc25 and consequently block the activation of the M-phase-promoting factor.