Transcript www.celanphy.science.ru.nl

the signal transduction machine
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the signal transduction machine
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G protein coupled receptors can be considered truly
signaling machines......
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the signal transduction machine
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and the more recently discovered -arrestin switch to
Src kinase signaling.
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and now for some other transmembrane signaling possibilities....
Consider a poly-proline region (pPro) in the C-terminal region of the metabotropic glutamate receptor
This has been shown to link to IP3 receptors via dimers of the scaffold protein Homer.
It remains to be established if this is a true signaling mechanism....
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Some Class A receptors have been shown to utilize a pPro region in the 3rd intracellular loop.....
to hook up with the adapter proteins Nck and Grh2.
For some receptors this has been shown to ultimately link up with MAP Kinases
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Some Class A receptors have been shown to link via their C-terminal with
PDZ-containing proteins such as the scaffold protein InaD.
This in turn can link up with various effector proteins on the membrane, such as enzymes or ion channels.
This has not yet been established as a true signaling mechanism.
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Another example is the -adrenergic receptor linking with the Na+/H+ exchanger
regulatory factor (NHERF)....
As the name suggests, this regulates the activity of a Na+/H+ exchanger on the membrane.
This has been established as a true signaling mechanism for the -adrenergic receptor.
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Yet another example is the serotonin 2B receptor linking with
constitutive NOS.
There is good evidence that this is a true physiological mechanism
for regulated generation of NO.
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Endothelial NOS has been shown to bind to some GPCRs in an
as yet undefined site in the 4th intracellular domain.
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With ligand binding the NOS comes free in an activated form, and thus
this mechanism can be considered a true signaling event.
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ARF
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PLD
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Finally, we have a Asn-Pro-X-X-Tyr motif in the 7th transmembrane region of some Class A receptors....
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This site can bind to and activate the small G proteins ARF and Rho,
which in turn activate phospholipase D (PLD).
This is believed to be a true signaling mechanism.
In
aD
NO
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the signal transduction machine
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Nck
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PLD
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In
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NO
GPCRs are truly remarkable signal transduction machines.
notes
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the signal transduction machine
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ARF
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ho
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PLD
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In
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