The pathway of MAP kinase mediation of CSF arrest in Xenopus oocytes.
A cytoplasmic activity in mature oocytes responsible for second meiotic metaphase arrest was identified over 30 years ago in amphibian oocytes. In Xenopus oocytes CSF activity is initiated by the progesterone-dependent synthesis of Mos, a MAPK kinase kinase, which activates the MAPK pathway. CSF arrest is mediated by a sole MAPK target, the protein kinase p90Rsk which leads to inhibition of cyclin B degradation by the anaphase-promoting complex. Rsk phosphorylates and activates the Bub1 protein kinase, which may cause metaphase arrest due to inhibition of the anaphase-promoting complex (APC) by a conserved mechanism defined genetically in yeast and mammalian cells. CSF arrest in vertebrate oocytes by p90Rsk provides a potential link between the MAPK pathway and the spindle assembly checkpoint in the cell cycle.
Maller
J L
JL
Howard Hughes Medical Institute and Department of Pharmacology, University of Colorado School of Medicine, Denver 80262, USA. Jim.Maller@uchsc.edu
Schwab
M S
MS
Roberts
B T
BT
Gross
S D
SD
Taieb
F E
FE
Tunquist
B J
BJ
D064173:Anaphase-Promoting Complex-Cyclosome; D000818:Animals; D008025:Ligases / Q000502:physiology; D016200:Maturation-Promoting Factor / Q000502:physiology; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology*; D009865:Oocytes / Q000254:growth & development / Q000502:physiology*; D011494:Protein Kinases / Q000502:physiology; D017231:Proto-Oncogene Proteins c-mos / Q000502:physiology*; D019893:Ribosomal Protein S6 Kinases; D008941:Spindle Apparatus; D043743:Ubiquitin-Protein Ligase Complexes; D014981:Xenopus
D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D011494:Protein Kinases; D017231:Proto-Oncogene Proteins c-mos; D019893:Ribosomal Protein S6 Kinases; D016200:Maturation-Promoting Factor; D020928:Mitogen-Activated Protein Kinases; D008025:Ligases