Page 155 - The Miracle of Hormones

Communication Within The Cell

This wonderful communication system is not limited to the nerve
cells; a similar system exists in our eyes. You are reading this book due in
large measure to the rapid communication system in the cells in your
eyes. This marvelous mechanism is also found in the eyes of animals.
Research on fruit flies has demonstrated that in this creature's compound
eye containing many smaller eyes, special communication modules exist.
The operation model of the special "InaD" messenger protein that causes
the transfer of visual messages from the eye to the brain of a fruit fly is
outlined below.
How did proteins establish such intelligent and particular communi-
cation systems? And how is it that proteins have constructed communica-
tion networks to respond immediately to the different needs of 100 trillion
cells? And again, how did the wonderfully designed module system agree

Light
Calcium channel Calcium
Activated G-protein

Rhodopsin
(light receptor)
Enzyme that
opens channel
PDZ domain

Enzyme that
InaD closes channel

Other proteins
involved in signaling

The eye of a fruit fly contains many smaller eyes and research has shown
that there are special communication modules within this mass of eyes.
Above you can see a simplified diagram of the operation of the special com-
munication protein called InaD, which affects the transfer of visual mes-
sages from the eye of a fruit fly to its brain.

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