Related Experiment Videos
Phosphorylation and protein synthetic events in Xenopus laevis oocytes microinjected with pp60v-src
Abstract:
Microinjection of purified pp60v-src, the transforming protein of Rous sarcoma virus, into Xenopus laevis oocytes accelerated the rate of progesterone- or insulin-induced meiotic maturation. This acceleration was abolished by incubating the oocytes with cycloheximide or puromycin during a 2-h interval between pp60v-src microinjection and progesterone addition. In contrast, exposure to actinomycin D did not alter the acceleration of maturation by microinjected pp60v-src. Associated with progesterone treatment and pp60v-src microinjection were a number of qualitative changes in phosphoproteins; a few of these changes are common to both stimuli. These results indicate that the action of pp60v-src in oocytes involves both phosphorylation and protein synthetic events that affect oocyte maturation.
Insights
Microinjection of pp60v-src protein accelerates Xenopus oocyte maturation. This effect requires new protein synthesis, indicating both phosphorylation and protein synthesis are key to maturation.
Area of Science:
- Cellular biology
- Developmental biology
- Virology
Background:
- pp60v-src is the transforming protein of Rous sarcoma virus.
- Meiotic maturation in Xenopus oocytes can be induced by progesterone or insulin.
Purpose of the Study:
- To investigate the role of pp60v-src in regulating meiotic maturation in Xenopus oocytes.
- To determine the molecular mechanisms by which pp60v-src influences oocyte maturation.
Main Methods:
- Microinjection of purified pp60v-src into Xenopus laevis oocytes.
- Treatment of oocytes with progesterone, insulin, cycloheximide, puromycin, and actinomycin D.
- Analysis of phosphoprotein changes associated with pp60v-src microinjection and hormonal stimulation.
Main Results:
- Microinjected pp60v-src accelerated progesterone- and insulin-induced meiotic maturation.
- This acceleration was blocked by cycloheximide and puromycin, but not actinomycin D.
- Both pp60v-src and hormonal treatments induced qualitative changes in phosphoproteins, with some overlap.
Conclusions:
- pp60v-src plays a role in accelerating Xenopus oocyte meiotic maturation.
- The action of pp60v-src involves both protein phosphorylation and protein synthesis.
- These findings highlight the complex interplay of signaling pathways in oocyte maturation.