Expression of the cell cycle control protein cdc25 in cleavage stage bovine embryos.
We have examined the synthesis and expression of a homologue of the cell cycle control protein cdc25 by early cleavage stage bovine embryos. cdc25 is the protein phosphatase responsible for activating p34cdc2 by dephosphorylating the threonine 14 (Thr 14) and tyrosine 15 (Tyr 15) residues of p34cdc2. Human cdc25 antibody was utilised in western blots and immunoprecipitations to examine the presence and synthesis of cdc25 in bovine embryos. cdc25 is present as a 52 kDa non-phosphorylated and a 66 kDa presumably phosphorylated form in bovine 1-, 2-, 4- and 8-cell embryos. However, cdc25 is actively synthesised only in 8-cell embryos, indicating that the cdc25 present prior to this stage is inherited from the oocyte. In addition, the synthesis of cdc25 was induced in 2-cell embryos in which cleavage was blocked with the DNA synthesis inhibitor aphidicolin.
Jones
J M
JM
Department of Meat and Animal Science, University of Wisconsin, Madison 53706, USA.
First
N L
NL
D000818:Animals; D016590:Aphidicolin / Q000494:pharmacology; D002417:Cattle / Q000196:embryology* / Q000235:genetics; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000096:biosynthesis* / Q000235:genetics; D002970:Cleavage Stage, Ovum / Q000201:enzymology*; D004261:DNA Replication / Q000187:drug effects; D004790:Enzyme Induction / Q000187:drug effects; D005307:Fertilization in Vitro; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D006801:Humans; D009865:Oocytes / Q000201:enzymology; D010749:Phosphoprotein Phosphatases / Q000096:biosynthesis* / Q000235:genetics; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D014158:Transcription, Genetic; D020687:cdc25 Phosphatases
D018797:Cell Cycle Proteins; D016590:Aphidicolin; D010749:Phosphoprotein Phosphatases; D020687:cdc25 Phosphatases