This activation can self renew the damages on injury, unlike induction of OCT4 and other iPS inducing genes. Cell can be programmed to self activate them on stimulus.
This is a complex question without a single answer. If a differentiated cell can activate a regeneration pathway? I think mammals have lost much of the regeneration potential of other organisms, however they still maintain some. It is theoretically possible to activate some inactive ones or replace them by ectopic gene expression. Ectopic reactivation of ES cell pluripotency factors is some times seen in tumors but this does not qualify as a normal regenerative process.
From my understanding of von Neumann's model, it is clearly the case that either the germ line never strays, or that a "reset" mechanism of the genetic message MUST EXIST. The only thing not known is the complexity of the process.
Regeneration in damaged tissues like kidney or liver occurs in response to injury or cell death. It is surviving differentiated cells that have the capacity to re-enter the mitotic cycle and repopulate damaged sites. In most cases there is not a population of stem cells waiting to be activated, rather it is more of a process of dedifferentiaton that now allows for proliferation to repair injury. If your question asks whether the genome had a specific regulatory region or set of gene for this process, I would guess that it does not. Rather each cell type has the ability to respond to injury, perhaps through loss of cell-cell contacts or secreted cytokines from infiltrating immune cells to sites of injury. Thus the environment at sites of injury can stimulate surviving cells to repopulate injured sites but this is likely to be very cell-type specific and not be controlled by a single mechanism common to all cells. If there is some commonality among cells, it is likely to be the regulation of cell cycle that now allows cells to renter s-phase and complete mitosis.
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