Q and G biography, Q and G discography
Embryonic cardiomyocyte hypoplasia and craniofacial defects in Gq.Department of Pathology, Amgen Inc.Heterotrimeric G proteins of the Gq class have been implicated in signaling pathways regulating cardiac growth under physiological and pathological conditions.Knockout mice carrying inactivating mutations in both of the widely expressed Gq class genes, Gq and G11, demonstrate that at least two active alleles of these genes are required for extrauterine life.These data demonstrate overlap in Gq and G11 gene functions and indicate that the Gq class of G proteins plays a crucial role in cardiac growth and development.Gq were used to identify residues in Gq that interact with GRK2.Q152A, a residue that structurally supports Switch III, are defective in binding GRK2.Interestingly, the model also predicts that residues in the helical domain of Gq interact with GRK2.T187K has greatly reduced binding to RGS2 and RGS4, it has little to no effect on binding to GRK2.Thus the RH domain A and C sites for Gq interaction rely on contacts with distinct regions and different Switch I residues in Gq.American Heart Association Scientist Development Grant 0235273N and a Research Corporation Cottrell Scholar grant (to J.National Institute of Health Grant GM44944 (to J.National Institute of Health Grant GM62884 (to P.The costs of publication of this article were defrayed in part by the payment of page charges.Section 1734 solely to indicate this fact.To whom correspondence should be addressed: Dept.Microbiology and Immunology, Kimmel Cancer Center, Thomas Jefferson University, 233 S.American Society for Biochemistry and Molecular Biology.Copyright notice Specificity of G alpha q and G alpha 11 gene expression in platelets and erythrocytes.Expressions of cellular differentiation and species differences.The receptor specificity of these alpha subunits is unknown.Studies of mouse and dog liver and human retina confirmed that the cDNA, primers and probes used could amplify and recognize G alpha 11 in other tissues.Compared with mouse cDNA, dog and human G alpha 11 cDNA had twice as many nucleotide substitutions (approx.Members of the Gq alpha subunit gene family activate phospholipase C beta isozymes.Berstein G, Blank JL, Smrcka AV, Higashijima T, Sternweis PC, Exton JH, Ross EM.Kozasa T, Hepler JR, Smrcka AV, Simon MI, Rhee SG, Sternweis PC, Gilman AG.Shenker A, Goldsmith P, Unson CG, Spiegel AM.The G protein coupled to the thromboxane A2 receptor in human platelets is a member of the novel Gq family.Johnson GJ, Leis LA, Dunlop PC.Proc Natl Acad Sci U S A.Activation of purified phospholipase C isozymes by G alpha subunits.Milligan G, Mullaney I, McCallum JF.Gq alpha and G11 alpha: absence of G11 alpha in human platelets and haemopoietically derived cell lines.Ushikubi F, Nakamura K, Narumiya S.Functional reconstitution of platelet thromboxane A2 receptors with Gq and Gi2 in phospholipid vesicles.Maurice DH, Waldo GL, Morris AJ, Nicholas RA, Harden TK.Proc Natl Acad Sci U S A.Willigen G, Donath J, Lapetina EG, Akkerman JW.Johnson GJ, Leis LA, Rao GH, White JG.Platelet adhesiveness in von Willebrand's disease.Gq and G11 are concurrently activated by bombesin and vasopressin in Swiss 3T3 cells.Proc Natl Acad Sci U S A.Proc Natl Acad Sci U S A.Rambhatla L, Patel B, Dhanasekaran N, Latham KE.Proc Natl Acad Sci U S A.Kesselring F, Spicher K, Porzig H.Pena P, del Camino D, Pardo LA, Dominguez P, Barros F.Xenopus oocytes to phospholipase C.Division of Pediatric
Endocrinology and Department of Pediatrics (M.Address all correspondence and requests for reprints to: Dr.Recombinant
mutations of Gq result in constitutive activation of phospholipase C
and have transforming activity.Importantly, our sample contains 8 FSH and LH adenomas.Gq
signaling cascade, making these tumors a logical choice for screening
for Gq mutations.Gq (Gq and
G11) has been identified as the G protein that mediates the TRH and
GnRH signal cascades in pituitary cells (2, 3).These pathways are
mediated by phospholipase C (PLC) and the inositol phospholipids.The most specific molecular abnormality in pituitary tumors identified
to date is a mutation of the G protein, Gs(4).Albright syndrome (4, 5, 6, 7, 8, 9, 10, 11, 12).Furthermore, Gq Q209L
mutations induce malignant transformation when expressed in NIH 3T3
cells (13, 14).Gq signaling
cascade, making these tumors a logical choice for screening for Gq
mutations.Purification of total RNA from pituitary tumor samples
Total RNA was isolated using an RNAgents Total RNA Isolation
System (Promega, Madison, WI).The purity and
quantity of RNA was analyzed spectrophotometrically.To avoid amplifying the Gq pseudogene,
which is highly homologous to human Gq cDNA, we designed
a pair of primers (20 oligonucleotides) that flanked the GTPase
catalytic domain from codon A168 to D243, which
had 3' mismatches with the pseudogene sequence.The
oligonucleotide primers were synthesized by Emory University
Microchemical Facility, Winship Cancer Center.DNA synthesis kit
(Boehringer Mannheim, Indianapolis, IN); total RNA (2.The total RNA was incubated at 65 C
for 15 min and cooled in ice for 5 min, the enzymes were added, and the
mixture was incubated at room temperature for 10 min and then at 42 C
for 60 min.Gq cDNA flanking the
catalytic domain from codon A168 to D243.PCR product was purified by eluting from agarose
gel using the Wizard PCR preps DNA purification system (Promega).PCR and SSCP analysis for screening of Gq
mutations
We used two strategies to eliminate the possibility of amplifying
the human Gq pseudogene that is highly homologous to human Gq
cDNA.Gq cDNA flanking the GTPase catalytic domain
from A168 to D243 and encompassing the target
codons of R183 and Q209 (Fig.The corresponding pseudogene
nucleotides are, respectively: G, G, A, T, and G.Therefore, we conclude that this set of primers
specifically amplifies the Gq cDNA product of 229 bp and reliably
excludes the pseudogene product.Schematic representation of amino acids,
regions of putative mutations, and primers for human Gq cDNA.DNA flanking both domains spanning
codon A168 to D243 and encompassing the target
codons R183 and Q209.To exclude the possibility of DNA contamination in RNA preparation, a
control PCR amplification was performed with RNA templates but without
RT.PCR products from all tumor samples.As in the published human Gq cDNA
from temporal cortex sequence cDNA (15), our sequencing clearly
revealed that Arg183 in the human Gq cDNA from 2 normal
pituitaries or from 37 pituitary tumors is coded by CGA, and
Gln209 by CAA.None of the presumed activating mutations at
codons Arg183 and Gln209 were detected.Furthermore, no alteration in the codons surrounding residues within
the GTPase catalytic domain between codons A168 and
D243 was detected.PCR products from pituitary tumors.The sequence is identical to the
published human cDNA sequence.Gln209 and the surrounding nucleotides.Furthermore, when
this mutant is expressed in NIH 3T3 cells, the cells are transformed,
as assessed by focus formation or the soft agar colony formation assay.Our study
analyzed 37 pituitary tumors of various types, and most importantly,
the samples in this study include 8 FSH and LH tumors.GnRH is the
releasing hormone for FSH and LH and is linked to Gq in pituitary
cell signaling (3).TSH tumors, most likely to harbor
Gq mutations.Furthermore, FSH and LH tumors are more prevalent than
TSH tumors, because they probably account for the majority of
clinically nonfunctioning pituitary adenomas (18).Despite these
tantalizing prospects, our results from direct DNA sequencing of 37
tumor samples, and those of Dong et al.PCR to screen for dominant oncogenic mutations is based
on the assumption that tumor cells express the mutant allele at levels
comparable with those of the normal allele.Another possibility is that dysregulation of
components downstream from Gq contribute to tumorigenesis.Inappropriate activation of other G proteins that might be coupled to
pituitary cell signaling pathways, including those that control
membrane Ca2+ conductance and MAP kinase activity, remain
to be explored.Alternative mechanisms, underlying pituitary
tumorigenesis , need to be explored.Department of Neuropathology, at
the Emory University Hospital, for the histology and
immunohistochemistry (IHC).Boothroyd CV, Grimmond SM, Cameron DP, Hayward NK.GTPase inhibiting mutations activate the alpha
chain of Gs and stimulate adenylyl cyclase in human pituitary tumours.Wu DQ, Lee CH, Rhee SG, Simon MI.Mutated alpha subunit of the Gq protein induces malignant
transformation in NIH 3T3 cells.Mutational activation and coupling
to receptors and phospholipase C.Davis F, Weintraub BD, et al."Please select an article (by clicking one or more article checkboxes) before proceeding."Quick links OMRON IA Proximity Sensors in your country.Please contact OMRON Europe B.GAPs) for heterotrimeric G protein subunits.Unlike the RGS box of p115 RhoGEF, the RGS box of LARG interacts not only with G12 and G13 but also with Gq.Superoxide Production in Cells Reconstituted with Angiotensin Type 1 Receptor and the Components of NADPH Oxidase.Ca2+ Signaling, and Cytoskeleton Modification in Head and Neck Squamous Cell Carcinoma Cells.Functional Tyr1306Cys Variant in LARG Is Associated With Increased Insulin Action in Vivo..Containing RhoGEF, in Vascular Smooth Muscle Cells.Coordinately Activate RhoA and Stress Fiber Formation following Receptor Stimulation.Rho Guanine Nucleotide Exchange Factors (GEFs) by G13.Jun Expression to Induce Cell Transformation.HT2A Serotonin Receptors Regulates Receptor Trafficking and Signal Transduction.Receptor Internalization Specifically Induced by Galpha q Signaling.
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