Disease relevance of Gnaz

• In contrast, the function and associated signal transduction cascade for the pertussis toxin insensitive G protein, Gz alpha have remained elusive [1].

High impact information on Gnaz

• Loss of signaling through the G protein, Gz, results in abnormal platelet activation and altered responses to psychoactive drugs [2].
• Indirect immunofluorescence using an antiserum directed against a peptide region present in Gz alpha, a PT-insensitive G protein, demonstrates positive immunoreactivity in the postacrosomal/lateral face region of the mouse sperm head [3].
• These data demonstrate that Gi protein alpha-subunits are present in the acrosomal region of mammalian sperm, consistent with their postulated role in regulating ZP3-mediated acrosomal exocytosis, and that PT-insensitive Gz alpha is found in a region of the sperm head distinct from that of the Gi alpha subunits [3].
• The potencies of beta-endorphin, [D-Ala2,N-MePhe4,Gly-ol5]-enkephalin (DAMGO) and [D-Pen2,5]enkephalin (DPDPE) were reduced after impairing the coupling of mu-ORs to Gi2 or Gz proteins [4].
• The affinity displayed by different opioids to mu receptors (ORs) was determined in mouse brain membranes incubated with antibodies directed to Galpha subunits of the guanine nucleotide-binding proteins Gi2 and Gz [4].

Biological context of Gnaz

• There has been recent evidence that Gz may play a role in the transmission of the neurotrophic signal from nerve terminals to the cell bodies [Johanson, S.O., Crouch, M.F., Hendry, I.A., Signal transduction from membrane to nucleus: the special case for neurons, Neurochem. Res. 21 (1996) 779-785] [5].
• Retrograde axonal transport of the alpha subunit of the GTP-binding protein Gz to the nucleus of sensory neurons [6].

Anatomical context of Gnaz

• We examined the developmental expression of the alpha subunit of Gz (Gzalpha) in the peripheral and central nervous systems of the mouse [5].
• These results suggest that Gz alpha exists in a protein complex with the actin cytoskeleton and an important intracellular signalling enzyme, PLC-gamma [1].
• 2. One such class of stable messengers may be the GTP-binding protein family and it has been shown that the alpha subunits of both Gi alpha and Gz alpha can be retrogradely transported in the mouse sciatic nerve [7].
• 3. Examination of the cell bodies in the dorsal root ganglia revealed that Gz alpha accumulated in the nucleus of cells with intact axons but that 24 h after axonal ligation this immunoreactivity decreased [7].

Other interactions of Gnaz

• Here we investigate the 5HT1A receptor in a mouse deficient in the alpha-subunit of Gz protein (Galphaz knock-out) [8].
• These proteins were subsequently identified as phospholipase C (PLC)-gamma, beta or gamma-actin, Gz alpha and G beta, the beta subunit of heterotrimeric G proteins, respectively [1].

Analytical, diagnostic and therapeutic context of Gnaz

• By Western blot analysis, we estimated that the amount of Gz alpha protein present in mouse islets was about 40% of that in retina [9].
• High doses of morphine promoted agonist desensitization even within the analgesia time-course, a phenomenon that appears to be related to the great capacity of morphine to activate Gz proteins [10].
• Influence of Gz and Gi2 transducer proteins in the affinity of opioid agonists to mu receptors [4].
• Furthermore, the levels seen in the nuclear compartment decline after axotomy or ligation of the mice under ether anaesthetic, suggesting it is the retrogradely transported Gz alpha that is accumulating in the nucleus after activation at the nerve terminal [6].
• The immunoprecipitation of four proteins (140, 46, 41 and 36 kDa) was shown to be inhibited in the presence of the Gz alpha peptide [1].

References