First published online November 7, 2007
Journal of Cell Science 120, 2202e (2007)
© The Company of Biologists Limited
Channelling stem cell energy
As embryonic stem cells (ESCs) differentiate, their metabolic requirements change–there is a shift from glycolysis to oxidative phosphorylation, and the number of mitochondria inside the cell increases in a lineage-specific way. On p. 4025, Justin St. John and colleagues investigate how ESCs coordinate these changes, analysing mitochondrial DNA (mtDNA) replication during differentiation of mouse ESCs. The researchers used real-time PCR to track the transcription of genes needed for mtDNA replication (such as POLG and Tfam) over this period. They find that the degree of ESC pluripotency correlates with mtDNA copy number and with the transcription of POLG and TFAM–and that this correlation varies in an ESC-line-specific way. They observe similar patterns when they use agents to direct differentiation towards certain cell fates. Using RNAi, they also show that POLG is required for the maintenance of pluripotency in ESCs. This supports the idea that a certain level of POLG is required to maintain pluripotency and that modulation of its activity can result in differentiation.
Related articles in JCS:
- Mitochondrial DNA replication during differentiation of murine embryonic stem cells
- Joao M. Facucho-Oliveira, Jon Alderson, Emma C. Spikings, Stuart Egginton, and Justin C. St. John
JCS 2007 120: 4025-4034.
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