NRC: G-proteins

How the NRC invented a new G protein - Gp
© 2006 PFPC

Throughout the 2006 NRC Review there are sections dealing with
G proteins.

While all of it “sounds” scientific, the issue is actually so poorly understood that at times one can only shake one‘s head in disbelief - how can the “highest scientific authority in the US” publish such nonsense?

Consider this example:

Under the Section: Neurotoxicity and Neurobehavioral Effects

NRC:

Using slices of rat neocortex, Jope (1988) found that NaF stimulated the hydrolysis of phosphoinositide by activation of a G protein, Gp. This protein acts as transducer between receptors and phospholipase C. (NRC Review, Page 184)

AND

It appears that many of fluoride's effects, and those of the aluminofluoride complexes are mediated by activation of Gp, a protein of the G protein family. (NRC Review, page 186)

FACT:

There is no such G protein called "Gp".

The G protein(s) the NRC should be discussing are called Gq/11.

It is Gq/11 which activate phospholipase C and which are responsible for the modulation of phosphoinositide hydrolysis as reported by Jope et al. (1994; 1997), as well as many others.

Gq/11 have been established to be the transducing G proteins for all Ca(2+)-mobilizing receptors (i.e. Exton,1993).

NRC:

More research is needed to clarify fluroide's biochemical effects on the brain.

FACT:

There are hundreds, if not thousands on studies, showing the effects of fluoride and clarifying the biochemical effects not only on the brain, but also on bone, dental fluorosis, etc.., all implicating Gq/11 - which are NOT pertussin-sensitive G proteins.

What is needed is NOT more research, but a scientific panel which actually understands the matter which it has been asked to review.

Surely, inventing a new G protein "Gp" is not a sign of any competence...

For more info, please see:

Gq/11

REFERENCES:

Exton JH - "Role of G proteins in activation of phosphoinositide phospholipase C" Adv Second Messenger Phosphoprotein Res 28:65-72 (1993)

Jope RS, Song L, Powers R - "[3H]PtdIns hydrolysis in postmortem human brain membranes is mediated by the G-proteins Gq/11 and phospholipase C-beta" Biochem J 304 ( Pt 2):655-9 (1994)

Jope RS, Song L, Li X, Powers R - "Impaired phosphoinositide hydrolysis in Alzheimer's disease brain" Neurobiol Aging 15(2):221-6 (1994)

Jope RS, Song L, Powers RE - "Cholinergic activation of phosphoinositide signaling is impaired in Alzheimer's disease brain" Neurobiol Aging 18
(1):111-20 (1997)