## Abstract The effect of inhibitors of RNA synthesis (Cordycepin, Actinomycin D) and protein synthesis (Cycloheximide) on the development and growth of mouse blastocysts in vitro was explored. Blastocysts exposed in vitro for 24 hours to 50 ฮผg/ml Cordycepin, 0.005 ฮผg/ml Actinomycin D, or 0.1 ฮผg/ml
Inhibition of RNA synthesis in embryo ofXenopus laevis by protease inhibitor
โ Scribed by Miyata, Shohei ;Shimazaki, Taketo ;Okamoto, Yoriyuki ;Motegi, Naoya ;Kitagawa, Mistuo ;Kihara, Hirozi K.
- Publisher
- John Wiley and Sons
- Year
- 1988
- Tongue
- English
- Weight
- 589 KB
- Volume
- 246
- Category
- Article
- ISSN
- 0022-104X
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โฆ Synopsis
We have studied the role of proteases during the development of Xenopus laevis embryos with the aid of protease inhibitors. The activity of proteases was found to be only minimal in the unfertilized egg and during the initiation of development, but activity began to increase at the morula stage. When the activity of proteases was inhibited by antipain, an inhibitor of endopeptidase activity, RNA synthesis in the embryo was inhibited. To examine the relationship between the inhibitory effect of antipain on protease activity and its effect on RNA synthesis, antipain was reduced with NaBH4 to inactivate its protease inhibitory activity. The reduced antipain did not inhibit RNA synthesis in the embryo. Antipain effectively inhibited synthesis of both rRNA and poly(A)+RNA but not 4S RNA. We therefore suggest that protease activity plays an important role in the initiation and/or continuation of RNA synthesis.
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