Short peer-review storytelling : One big technical problem of human embryonic stem cells (hESCs) (in contrast to mouse embryonic stem cells) that hESCs normally undergo high rates of spontaneous apoptosis and differentiation, making them difficult to maintain in culture. Now we are getting to know a bit more on the molecular background of these processes. In an article in the prestigious Journal of Biological Chemistry Qin et al.’s studies reveal the important roles of p53 as a critical mediator of human embryonic stem cells survival and differentiation.
Regulation of apoptosis and differentiation by p53 in human embryonic stem cells.
J Biol Chem. 2007 Feb 23;282(8):5842-52
“Here we demonstrate that p53 protein accumulates in apoptotic hESCs induced by agents that damage DNA. However, despite the accumulation of p53, it nevertheless fails to activate the transcription of its target genes. This inability of p53 to activate its target genes has not been observed in other cell types, including mESCs. We further demonstrate that p53 induces apoptosis of hESCs through a mitochondrial pathway. Reducing p53 expression in hESCs in turn reduces both DNA damage-induced apoptosis as well as spontaneous apoptosis. Reducing p53 expression also reduces spontaneous differentiation and slows the differentiation rate of hESCs.”
Figure 2 for the pros:
