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Updated: Jun 26, 2026
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Application of RNAi and Heat-shock-induced Transcription Factor Expression to Reprogram Germ Cells to Neurons in C. elegans
Published on: January 1, 2018
Nuclear reprogramming in heterokaryons is rapid, extensive, and bidirectional.
Adam Palermo1, Regis Doyonnas, Nidhi Bhutani
1Department of Microbiology and Immunology and Stem Cell Institute, Stanford University School of Medicine, 269 Campus Dr., Stanford, CA 94305-5175, USA.
Summary
Nuclear reprogramming in fused cells (heterokaryons) is rapid and extensive, occurring within hours and days. The cell type with the greater number of regulators dictates the reprogramming outcome, showing bidirectional control.
Area of Science:
- Cell Biology
- Genetics
- Regenerative Medicine
Background:
- Nuclear reprogramming is crucial for regenerative medicine applications.
- Previous studies lacked detailed assessment of reprogramming kinetics due to technological limitations.
Purpose of the Study:
- To assess the time course and extent of nuclear reprogramming in fused cells (heterokaryons).
- To investigate the dominance of cell phenotypes during reprogramming.
Main Methods:
- Development of species-specific transcriptome amplification (SSTA) to resolve transcripts from fused human and mouse cells.
- Analysis of gene activation and repression in heterokaryons over time.
Main Results:
- Hundreds of genes were activated or repressed within hours of cell fusion.
- Extensive transcriptional changes were observed within 4 days.
- Reprogramming outcome was bidirectional and dependent on the relative abundance of keratinocytes and muscle cells.
Conclusions:
- Nuclear reprogramming in heterokaryons is a rapid and extensive process.
- The balance of regulatory factors determines the dominant cell phenotype.
- Findings provide fundamental insights into nuclear reprogramming for regenerative medicine.
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