Characterization of soluble forms of nonchimeric  type V adenylyl cyclases

Scholich, Klaus; Barbier, Ann; Mullenix, Jason B.; Patel, Tarun B.

doi:10.1073/pnas.94.7.2915

Cited by 69 publications

(79 citation statements)

References 39 publications

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“…The AC levels were identical in wild-type and Gnal + /À mice ( Figure 1i). Altogether these results show that the mutation of Gaolf did not alter the levels of AC5 and that the decreased basal and Mn 2 + -sensitive cyclase activity reflect the decrease in stimulatory G protein, as even the Mn 2 + -stimulated AC remains sensitive to the presence of G protein (Bender and Neer, 1983;Scholich et al, 1997).…”

Section: Dopamine-stimulated Ac Activity Is Decreased Inmentioning

confidence: 92%

Quantitative Changes in Gαolf Protein Levels, but not D1 Receptor, Alter Specifically Acute Responses to Psychostimulants

Corvol

Valjent

Pascoli

et al. 2006

Neuropsychopharmacol

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Striatal dopamine D1 receptors (D1R) are coupled to adenylyl cyclase through Gaolf. Although this pathway is involved in important brain functions, the consequences of quantitative alterations of its components are not known. We explored the biochemical and behavioral responses to cocaine and D-amphetamine (D-amph) in mice with heterozygous mutations of genes encoding D1R and Gaolf (Drd1a + /À and Gnal + /À), which express decreased levels of the corresponding proteins in the striatum. Dopamine-stimulated cAMP production in vitro and phosphorylation of AMPA receptor GluR1 subunit in response to D-amph in vivo were decreased in Gnal + /À, but not Drd1a + /À mice. Acute locomotor responses to D1 agonist SKF81259, D-amph and cocaine were altered in Gnal + /À mice, and not in Drd1a + /À mice. This haploinsufficiency showed that Gaolf but not D1R protein levels are limiting for D1R-mediated biochemical and behavioral responses. Gnal + /À mice developed pronounced locomotor sensitization and conditioned locomotor responses after repeated injections of D-amph (2 mg/kg) or cocaine (20 mg/kg). They also developed normal D-amph-conditioned place preference. The D1R/cAMP pathway remained blunted in repeatedly treated Gnal + /À mice. In contrast, D-amph-induced ERK activation was normal in the striatum of these mice, possibly accounting for the normal development of long-lasting behavioral responses to psychostimulants. Our results clearly dissociate biochemical mechanisms involved in acute and delayed behavioral effects of psychostimulants. They identify striatal levels of Gaolf as a key factor for acute responses to psychostimulants and suggest that quantitative alterations of its expression may alter specific responses to drugs of abuse, or possibly other behavioral responses linked to dopamine function.

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Section: Dopamine-stimulated Ac Activity Is Decreased Inmentioning

confidence: 92%

Quantitative Changes in Gαolf Protein Levels, but not D1 Receptor, Alter Specifically Acute Responses to Psychostimulants

Corvol

Valjent

Pascoli

et al. 2006

Neuropsychopharmacol

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“…32). The proteins were expressed in the Escherichia coli strain TP2000, which is incapable of producing cAMP (42).…”

Section: Methodsmentioning

confidence: 99%

“…(31), although higher concentrations were not explored. Recently, a chimeric, soluble form of AC5, comprising its fused cytosolic (C1 and C2) domains was reported to display high affinity inhibition by Ca 2ϩ , which was lost upon truncation of the C1 region (32). Furthermore, AC2, which is classified as a Ca 2ϩ -insensitive adenylyl cyclase, displays inhibition in response to high concentrations of Ca 2ϩ .…”

Section: ؉mentioning

confidence: 99%

Inhibition by Calcium of Mammalian Adenylyl Cyclases

Guillou

Nakata

Cooper

1999

Journal of Biological Chemistry

110

108

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Ca2؉ regulates mammalian adenylyl cyclases in a type-specific manner. Stimulatory regulation is moderately well understood. By contrast, even the concentration range over which Ca 2؉ inhibits adenylyl cyclases AC5 and AC6 is not unambiguously defined; even less so is the mechanism of inhibition. In the present study, we compared the regulation of Ca 2؉ -stimulable and Ca 2؉ -inhibitable adenylyl cyclases expressed in Sf9 cells with tissues that predominantly express these activities in the mouse brain. Soluble forms of AC5 containing either intact or truncated major cytosolic domains were also examined. All adenylyl cyclases, except AC2 and the soluble forms of AC5, displayed biphasic Ca 2؉ responses, suggesting the presence of two Ca 2؉ sites of high (ϳ0.2 M) and low affinity (ϳ0.1 mM). With a high affinity, Ca 2؉ (i) stimulated AC1 and cerebellar adenylyl cyclases, (ii) inhibited AC6 and striatal adenylyl cyclase, and (iii) was without effect on AC2. With a low affinity, Ca 2؉ inhibited all adenylyl cyclases, including AC1, AC2, AC6, and both soluble forms of AC5. The mechanism of both high and low affinity inhibition was revealed to be competition for a stimulatory Mg 2؉ site(s). A remarkable selectivity for Ca 2؉ was displayed by the high affinity site, with a K i value of ϳ0.2 M, in the face of a 5000-fold excess of Mg 2؉. The present results show that high and low affinity inhibition by Ca 2؉ can be clearly distinguished and that the inhibition occurs type-specifically in discrete adenylyl cyclases. Distinction between these sites is essential, or quite spurious inferences may be drawn on the nature or location of high affinity binding sites in the Ca 2؉ -inhibitable adenylyl cyclases.Profound physiological significance derives from the regulation of adenylyl cyclase by Ca 2ϩ

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“…2 and 3). The N-terminal domain of ACV did not exert a significant effect on the enzymatic properties or on certain regulatory modes (such as the inhibition mediated by G␣ i or calcium (12,35)). Replacement of the N terminus of ACVI with that of ACV did not affect the enzymatic properties of ACVI either (Table I) but markedly altered the inhibition mediated by D2s-R (Fig.…”

Section: Discussionmentioning

confidence: 99%

“…For example, the C1b domain has been implicated in the regulation of AC isozymes mediated by Ca 2ϩ /calmodulin, calcineurin, or protein kinase A (8 -11). In addition, the C1b domain of ACV and ACVII has been shown to modulate G␣ s -evoked activation by interacting with catalytic core complexes (12,13). Others and we have shown that another variable region, the N-terminal domain, also significantly contributes to the regulation of AC activity (14,15).…”

mentioning

confidence: 95%

An Important Functional Role of the N Terminus Domain of Type VI Adenylyl Cyclase in Gαi-mediated Inhibition

Kao

Lai

Hwang

et al. 2004

Journal of Biological Chemistry

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The mammalian adenylyl cyclase (AC) 1 superfamily consists of nine membrane-bound isoforms. All of these possess three large cytosolic domains (designated N, C1a, and C2 domains; Fig. 1A), which are separated by two sets of six-transmembrane domains (1-3). The C1a and C2 domains among the nine AC members are highly homologous (with 50 -90% similarity in amino acids). In addition, the C1a and C2 domains of each AC share ϳ50% similarity and form the catalytic core complex, which can be stimulated by forskolin or G␣ s proteins (4 -6). Crystallographic analysis of the catalytic complex consisting of the C1a domain, the C2 domain, and the GTP␥S-bound G␣ s protein revealed that forskolin and/or G␣ s stimulate ACs by enhancing the interaction between the C1a and C2 domains and by stabilizing the C1a-C2 catalytic core complex (7).Although most ACs can be activated by G␣ s and forskolin, regulation of each AC isozyme differs. Studies of the morevariable N and C1b domains reveal that these two domains may play important regulatory roles. For example, the C1b domain has been implicated in the regulation of AC isozymes mediated by Ca 2ϩ /calmodulin, calcineurin, or protein kinase A (8 -11). In addition, the C1b domain of ACV and ACVII has been shown to modulate G␣ s -evoked activation by interacting with catalytic core complexes (12, 13). Others and we have shown that another variable region, the N-terminal domain, also significantly contributes to the regulation of AC activity (14, 15). Specifically, the N-terminal domain of ACVI (amino acids 1-160) plays an important role in the protein kinase C (PKC)-mediated inhibition and phosphorylation of ACVI (14). Removal of the first 86 amino acids (aa) of ACVI reduced the inhibitory effect of PKC on ACVI activity without affecting the basic enzymatic properties, including the affinities toward its substrate and two stimuli (forskolin and G␣ s protein (14)). The N-terminal domain of ACVI therefore functions as a regulatory domain. Further biochemical analyses revealed that at least four PKC phosphorylation sites (Ser-10, Ser-568, Ser-674, and Thr-931), located in the three large cytosolic domains of ACVI, significantly contribute to PKC-mediated inhibition of ACVI (16). Intramolecular interactions among the N, C1a/b, and C2 domains of ACVI therefore appear to be important for regulation of ACVI activity.G␣ i -mediated inhibition is a major regulatory feature of the AC superfamily. Among AC members, only ACI, ACV, and ACVI can effectively be inhibited by G␣ i proteins (17, 18). Based on results obtained from an in vitro binding assay, the C1a domain was shown to bind myristoylated G␣ i proteins and form stable complexes (19,20). Mutagenesis of full-length ACV in the ␣2 and ␣3 helices of the C1a domain revealed several residues important for the inhibition by G␣ i proteins. It was postulated that G␣ i may exert its inhibitory effect through binding to the C1a domain at the site just opposite the G␣ sbinding site on the C2 domain and, subsequently, causes reduced interaction between ...

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Characterization of soluble forms of nonchimeric type V adenylyl cyclases

Cited by 69 publications

References 39 publications

Quantitative Changes in Gαolf Protein Levels, but not D1 Receptor, Alter Specifically Acute Responses to Psychostimulants

Quantitative Changes in Gαolf Protein Levels, but not D1 Receptor, Alter Specifically Acute Responses to Psychostimulants

Inhibition by Calcium of Mammalian Adenylyl Cyclases

An Important Functional Role of the N Terminus Domain of Type VI Adenylyl Cyclase in Gαi-mediated Inhibition

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