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Nuclear actin and transcriptional activation
1Wellcome Trust/Cancer Research UK Gurdon Institute; University of Cambridge; Tennis Court Road, Cambridge UK.
Communicative & Integrative Biology
|November 3, 2011
Summary
Nuclear reprogramming reverses differentiated cells to an embryonic state by reactivating genes like Oct4. This study highlights polymerized nuclear actin
Area of Science:
- Cell biology
- Developmental biology
- Gene regulation
Background:
- Differentiated cells normally do not revert to an embryonic state.
- Nuclear reprogramming can reverse differentiated cells to an embryonic state.
- Reactivation of embryonic genes, such as Oct4 (Pou5f1), is crucial for reprogramming.
Purpose of the Study:
- To elucidate factors and mechanisms responsible for transcriptional reprogramming.
- To investigate the role of nuclear actin in transcriptional reactivation of Oct4.
Main Methods:
- Transplantation of mammalian somatic nuclei into Xenopus laevis oocyte nucleus (germinal vesicle, GV).
- Observation of polymerized actin within transplanted nuclei.
- Analysis of Oct4 gene reactivation.
Main Results:
- Polymerized actin is abundantly present in nuclei transplanted into the Xenopus oocyte nucleus.
- Nuclear actin plays an important role in the transcriptional reactivation of Oct4.
- This study emphasizes a significant contribution of nuclear actin in transcriptional activation.
Conclusions:
- Nuclear actin is a key factor in transcriptional reprogramming.
- Possible roles of nuclear actin in transcriptional activation in Xenopus oocytes and other cell types are discussed.
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