for an example of 'functional multiplexing', as it's discussed in AoK, Ap9,
see:
http://www.eurekalert.org/releases/mgh-rfm072099.html
from the press release:
"Two things are curious about the identification of a cyptochrome as an
essential part of a negative feedback loop in the inner workings of the
mammalian clock. One is that its role could never have been predicted based
on the structure of the protein itself. Cryptochromes are a family of
light-sensing proteins. Who would have guessed that such a protein would
function in a light-independent manner to regulate per? The second curious
aspect of the finding is that cryptochromes play an entirely different (and
more predictable) role in regulating the rhythms of plants and flies where
they form the critical light sensors that reset the biological clock in
response to light. Just as a Rolex keeps time according to its own inner
machinery and yet can be reset to a new time zone by a turn of a knob, so
too can the intrinsic machinery of the biological clock be reset by light.
The identification that the resetting knob of one clock makes up part of the
inner workings of another is certainly surprising and unprecedented."
False and False... as is explained in AoK.
K. P. Collins
