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The Body Electric
called puromycin, blocks the transfer of information from messenger
RNA to the ribosomes and thus prevents proteins from being built. Dan
proposed that we set up our plastic chambers in pairs. In one member of
each pair we would place blood cells in saline solution and pass current
through them as before. The other chamber would contain cells from the
same frog and be connected to the same generator, but the solution
would contain puromycin. The setup would thus be precisely controlled.
If the current was actually unlocking new genes, the puromycin should
stop dedifferentiation by intercepting the DNA's protein-making in-
structions. If the current was merely making the cells degenerate, how-
ever, the puromycin should have no effect and the transformations
should continue.
Our conclusion held up: The cells in the puromycin solution didn't
change. Next Dan suggested that we bathe these cells with several
changes of water to wash out the puromycin. They promptly dedifferen-
tiated with no current flowing! Apparently the current caused the ge-
netic change in spite of the antibiotic, and the genes stayed unlocked, so
the system still worked perfectly as soon as the puromycin blockade was
THE RNA BLOCKADE CONFIRMS ELECTRICAL DEDIFFERENTIATION
By early
1970 we had solid proof for nearly every detail of the control
system for fracture healing in frogs, and by extension probably in mam-
mals as well. Like all other injuries, a fracture produced a current of
injury, in this case derived from
the nerves in and around the per-