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Updated: May 23, 2026
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Reprogramming Primary Amniotic Fluid and Membrane Cells to Pluripotency in Xeno-free Conditions
Published on: November 27, 2017
Embryonic stem cells induce pluripotency in somatic cell fusion through biphasic reprogramming
Kara M Foshay1, Timothy J Looney, Sheila Chari
1Department of Human Genetics, University of Chicago, Howard Hughes Medical Institute, Chicago, IL 60637, USA.
Molecular Cell
|March 27, 2012
Summary
Cell fusion reprograms genes, but cis-silenced genes only reprogram when fused with embryonic stem cells (ESCs). ESCs possess a unique cis-reprogramming capacity distinguishing them from somatic cells.
Area of Science:
- Cell Biology
- Developmental Biology
- Genetics
Background:
- Cell fusion is known to reprogram gene expression.
- Gene silencing in somatic cells can be attributed to trans-acting factors or cis-acting chromatin.
- The extent of reprogramming and its dependence on cell types remain unclear.
Purpose of the Study:
- To investigate the reprogramming of trans- and cis-silenced genes during cell fusion.
- To compare reprogramming in somatic-somatic cell fusions versus somatic-embryonic stem cell (ESC) fusions.
- To elucidate the distinct phases of reprogramming mediated by ESCs.
Main Methods:
- Fusion of somatic cells with other somatic cells or with ESCs.
- Analysis of gene expression changes following cell fusion.
- Distinguishing between trans- and cis-silencing mechanisms.
Main Results:
- Reprogramming of trans-silenced genes occurs in both somatic-somatic and somatic-ESC fusions.
- Reprogramming of cis-silenced genes is specific to somatic-ESC fusions.
- ESCs exhibit rapid, replication-independent trans-reprogramming and slow, replication-dependent cis-reprogramming.
- Pluripotency genes Oct4 and Nanog are cis-silenced in somatic cells.
Conclusions:
- Cis-reprogramming is a key functional difference between ESCs and somatic cells.
- ESCs possess a unique ability to reprogram cis-silenced genes in somatic genomes.
- The cell type involved in fusion critically determines the extent and mechanism of gene reprogramming.
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