Identification of Modulators of Mammalian G-Protein Signaling by Functional Screens in the Yeast Saccharomyces cerevisiae

Cismowski, Mary J.; Takesono, Aya; Ma, Chienling; Lanier, Stephen M.; Duzic, Emir

doi:10.1016/s0076-6879(02)44712-x

Cited by 15 publications

(16 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using simple growth assays on selective media containing glucose (no cDNA induction) or galactose (cDNA induction) and yeast strains with deletions or modifications of their pheromone signaling pathways we could determine whether the bioactivity of these cDNAs required G␤␥ or acted downstream of G protein to influence pathway activation (Figs. 1 and 5) (12,13,19). In such epistasis experiments, nine of the cDNAs required G␤␥ for their activity and thus were consistent with the definition of a receptorindependent activator of G protein signaling ( Table 1).…”

Section: Resultssupporting

confidence: 63%

“…This screen uses an expression cloning strategy in Saccharomyces cerevisiae to select for receptor-independent activators of the pheromone response pathway in which heterotrimeric G proteins regulate a mitogen-activated protein kinase cascade controlling yeast mating and growth (Fig. 5, which is published as supporting information on the PNAS web site) (12,13,19). Our strategy involved the use of a modified yeast strain lacking the pheromone receptor and containing mammalian G␣ (G␣ i3 , G␣ s , or G␣ 16 ) in place of the yeast G␣ subunit.…”

Section: Resultsmentioning

confidence: 99%

“…The yeast strain was further modified to respond to activation of the G protein regulated signaling cascade with a readout of growth. This modification allowed us to rapidly screen mammalian cDNA libraries constructed in a galactose-inducible vector for activators of this signaling cascade by selecting for those promoting growth in a galactose-specific manner (12,13,19). cDNAs isolated with this strategy that required the presence of heterotrimeric G protein for bioactivity were termed AGS proteins and thus are functionally defined rather than based on any conserved protein sequences.…”

Section: Resultsmentioning

confidence: 99%

“…A human prostate leiomyosarcoma cDNA library in pCMVSport6 (Invitrogen) and ProQuest normalized human heart cDNA library in pEXP-AD502 (Invitrogen) were swapped into pYES-DEST52 (Invitrogen) by recombination. Functional screens and growth assays in modified strains of S. cerevisiae were conducted as described (12,13,19).…”

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Identification of a receptor-independent activator of G protein signaling (AGS8) in ischemic heart and its interaction with Gβγ

Sato

Cismowski

Toyota

et al. 2006

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

As part of a broader effort to identify postreceptor signal regulators involved in specific diseases or organ adaptation, we used an expression cloning system in Saccharomyces cerevisiae to screen cDNA libraries from rat ischemic myocardium, human heart, and a prostate leiomyosarcoma for entities that activated G protein signaling in the absence of a G protein coupled receptor. We report the characterization of activator of G protein signaling (AGS) 8 (KIAA1866), isolated from a rat heart model of repetitive transient ischemia. AGS8 mRNA was induced in response to ventricular ischemia but not by tachycardia, hypertrophy, or failure. Hypoxia induced AGS8 mRNA in isolated adult ventricular cardiomyocytes but not in rat aortic smooth muscle cells, endothelial cells, or cardiac fibroblasts, suggesting a myocyte-specific adaptation mechanism involving remodeling of G protein signaling pathways. The bioactivity of AGS8 in the yeast-based assay was independent of guanine nucleotide exchange by G␣, suggesting an impact on subunit interactions. Subsequent studies indicated that AGS8 interacts directly with G␤␥ and this occurs in a manner that apparently does not alter the regulation of the effector PLC-␤ 2 by G␤␥. Mechanistically, AGS8 appears to promote G protein signaling by a previously unrecognized mechanism that involves direct interaction with G␤␥.accessory protein ͉ signal adaptation ͉ hypoxia

show abstract

Section: Resultssupporting

confidence: 63%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Identification of a receptor-independent activator of G protein signaling (AGS8) in ischemic heart and its interaction with Gβγ

Sato

Cismowski

Toyota

et al. 2006

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

show abstract

“…This protein activates both heterotrimeric brain G-protein and free Gα and exhibits mechanistic properties that are distinct from receptor-mediated activation of G-protein (Ribas et al, 2002b). The second approach involved an expression cloning system utilizing the pheromone response pathway in S. cerevisiae (Cao et al, 2004;Cismowski et al, 2002;Cismowski et al, 1999;Sato et al, 2006b;Takesono et al, 1999).…”

Section: Strategy To Identify Receptor-independent Activators Of G-prmentioning

confidence: 99%

Mechanistic pathways and biological roles for receptor-independent activators of G-protein signaling

Blumer

Smrcka

Lanier

2007

Pharmacology & Therapeutics

Self Cite

122

View full text Add to dashboard Cite

Signal processing via heterotrimeric G-proteins in response to cell surface receptors is a central and much investigated aspect of how cells integrate cellular stimuli to produce coordinated biological responses. The system is a target of numerous therapeutic agents, plays an important role in adaptive processes of organs, and aberrant processing of signals through these transducing systems is a component of various disease states. In addition to GPCR-mediated activation of G-protein signaling, nature has evolved creative ways to manipulate and utilize the Gαβγ heterotrimer or Gα and Gαβγ subunits independent of the cell surface receptor stimuli. In such situations, the G-protein subunits (Gα and Gαβγ) may actually be complexed with alternative binding partners independent of the typical heterotrimeric Gαβγ. Such regulatory accessory proteins include the family of RGS proteins that accelerate the GTPase activity of Gα and various entities that influence nucleotide binding properties and/or subunit interaction. The latter group of proteins includes receptor independent activators of G-protein signaling or AGS proteins that play surprising roles in signal processing. This review provides an overview of our current knowledge regarding AGS proteins. AGS proteins are indicative of a growing number of accessory proteins that influence signal propagation, facilitate cross talk between various types of signaling pathways and provide a platform for diverse functions of both the heterotrimeric Gαβγ and the individual Gα and Gαβγ subunits.

show abstract

Reviews of Physiology Biochemistry and Pharmacology

2005

Reviews of Physiology, Biochemistry, and Pharmacology

View full text Add to dashboard Cite

During protein translation, a variety of quality control checks ensure that the resulting polypeptides deviate minimally from their genetic encoding template. Translational fidelity is central in order to preserve the function and integrity of each cell. Correct termination is an important aspect of translational fidelity, and a multitude of mechanisms and players participate in this exquisitely regulated process. This review explores our current understanding of eukaryotic termination by highlighting the roles of the different ribosomal components as well as termination factors and ribosome-associated proteins, such as chaperones.Abbreviations aa-tRNA: Amino-acyl tRNA · eLF: Eukaryotic translation initiation factor · IF: Prokaryotic translation initiation factor · eEF: Eukaryotic translation elongation factor · EF: Prokaryotic translation elongation factor · eRF: Eukaryotic translation termination factor (release factor) · RF: Prokaryotic translation release factor · RRF: Ribosome recycling factor · Rps: Protein of the prokaryotic small ribosomal subunit · Rpl: Protein of the eukaryotic large ribosomal subunit · S: Protein of the prokaryotic small ribosomal subunit · L: Protein of the prokaryotic large ribosomal subunit · PTC: Peptidyl transferase center · RNC: Ribosome-nascent chain-mRNA complex · ram: Ribosomal ambiguity mutation · RAC: Ribosome-associated complex · NMD: Nonsense-mediated mRNA decay Abstract The aquaporins (AQPs) are small integral membrane proteins that transport water and in some cases small solutes such as glycerol. Physiological roles of the ten or more mammalian AQPs have been proposed based on their expression in epithelial, endothelial and other tissues, their regulation, and in some cases the existence of humans with AQP mutation. Here, the role of AQPs in mammalian physiology is reviewed, based on phenotype analysis of transgenic mouse models of AQP deletion/mutation. Phenotype studies support the predicted roles of AQPs in kidney tubule and microvessel fluid transport for urinary concentrating function, and in fluid-secreting glandular epithelia. The phenotype studies have also shown unexpected roles of AQPs in brain and corneal swelling, in neural signal transduction, in regulation of intracranial and intraocular pressure, and in tumor angiogenesis and cell migration. The water/glycerol-transporting AQPs were found to play unexpected roles in skin hydration and in fat metabolism. However, many phenotype studies were negative, such as normal airway/lung and skeletal muscle function, despite AQP expression, indicating that tissue-specific AQP expression does not indicate physiological significance. The mouse phenotype data suggest that modulators of AQP expression/function may have such wide-ranging clinical applications as diuretics and in the treatment of brain swelling, glaucoma, epilepsy, obesity, and cancer. Rev Physiol Biochem Pharmacol (2005) 155:57-80 Abstract Heterotrimeric G-proteins are key transducers for signal transfer from outside the cell, mediating signals emanating...

show abstract

Identification of Modulators of Mammalian G-Protein Signaling by Functional Screens in the Yeast Saccharomyces cerevisiae

Cited by 15 publications

References 36 publications

Identification of a receptor-independent activator of G protein signaling (AGS8) in ischemic heart and its interaction with Gβγ

Identification of a receptor-independent activator of G protein signaling (AGS8) in ischemic heart and its interaction with Gβγ

Mechanistic pathways and biological roles for receptor-independent activators of G-protein signaling

Reviews of Physiology Biochemistry and Pharmacology

Contact Info

Product

Resources

About