Two sensitivity levels of cattle oocytes to puromycin.

摘要: Germinal vesicle breakdown (GVBD) in cumulus-enclosed and denuded cattle oocytes was sensitive to puromycin at concentrations or above 50 micrograms/ml. Media supplemented with 5-25 micrograms/ml of did not significantly reduce either rate sequence GVBD after 8 h culture (82-96% GVBD). In 50, 75, 100 micrograms/ml, occurred 15, 4, 2% oocytes, respectively. However, micrograms puromycin/ml postpone the time GVBD, since all treated underwent 20 culture. Oocytes arrested germinal (GV) stage possessed GV filled highly condensed bivalents. The block (100 micrograms/ml) fully reversible, two times faster than control medium. Proteins important for were synthesized during first 4 culture, 81% when added preincubation polar body (I PB) expulsion more inhibition protein synthesis, as shown by observation that 2.5 5 (69 61%) reduced incidence Metaphase II, 10 (31%) it. I PB 25 37 less 5%. subsequent (8 h) 6-dimethylaminopurine proved nuclear membrane is phosphorylation process chromatin condensation.