Differential regulation of NPR-B/GC-B by protein kinase c and calcium

Abbey-Hosch, Sarah E.; Smirnov, Dmitri; Potter, Lincoln R.

doi:10.1016/j.bcp.2005.04.034

Cited by 31 publications

(25 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is also consistent with early observations showing that adenine analogs that cause prolonged phosphorylation, such as ATPγS, stimulate the enzyme to a greater extent than do ATP analogs that are not kinase substrates, such adenylyl-imidodiphosphate (27, 42). Subsequent experiments showed that thiophosphorylated ATP analogs and phosphatase inhibitors increased the phosphate content and activity of GC-A and GC-B, confirming that the inclusion of ATP analogs in GC assays increased phosphorylation of the enzyme (34, 46, 47). …”

Section: Discussionmentioning

confidence: 81%

Guanylyl Cyclases A and B Are Asymmetric Dimers That Are Allosterically Activated by ATP Binding to the Catalytic Domain

Robinson

Potter

2012

Sci. Signal.

Self Cite

View full text Add to dashboard Cite

It is not known how natriuretic peptides and adenosine triphosphate (ATP) activate guanylyl cyclase A (GC-A) and GC-B, which generate the second messenger cyclic guanosine monophosphate. We determined that natriuretic peptides increased the maximum rate of these enzymes >10-fold in a positive cooperative manner in the absence of ATP. In the absence of natriuretic peptides, ATP shifted substrate-velocity profiles from cooperative to linear but did not increase the affinity of GCs for the substrate guanosine triphosphate (GTP) since the Michaelis constant was unchanged. However, in the presence of natriuretic peptides, ATP competed with GTP for binding to an allosteric site, which enhanced the activation of GCs by decreasing the Michaelis constant. Thus, natriuretic peptide binding was required for communication of the allosteric activation signal to the catalytic site. The ability of ATP to activate GCs decreased and enzyme potency (a measure of sensitivity to stimulation) increased with increasing GTP concentrations. Point mutations in the purine-binding site of the catalytic domain abolished GC activity but not allosteric activation. Coexpression of inactive mutants produced half the activity expectedfor symmetric catalytic dimers. 2′-Deoxy-ATP and 2′-deoxy-GTP were poorallosteric activators, but 2′-deoxy-GTP was an effective substrate, consistent with distinct binding requirements for the allosteric and catalytic sites. We conclude that membrane GC domains are asymmetric homodimers with distinct and reciprocally regulated catalytic and allosteric sites that bind to GTP and ATP, respectively. These data define a new membrane GC activation model and provide evidence of a previously unidentified GC drug interaction site.

show abstract

Section: Discussionmentioning

confidence: 81%

Guanylyl Cyclases A and B Are Asymmetric Dimers That Are Allosterically Activated by ATP Binding to the Catalytic Domain

Robinson

Potter

2012

Sci. Signal.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The alanine, but not the glutamate, mutation decreased hormone-dependent cyclase activity (Figure 4C). In addition, the T529E mutation was introduced into a receptor containing glutamate substitutions at all five previously identified phosphorylation sites (GC-B-5E) (23, 24) to generate a receptor containing six glutamates (GC-B-6E). CNP-dependent guanylyl cyclase activity was significantly higher in membranes from cells expressing GC-B-6E compared to cells expressing GC-B-5E (Figure 4D).…”

Section: Resultsmentioning

confidence: 99%

Mass Spectrometric Identification of Phosphorylation Sites in Guanylyl Cyclase A and B

Yoder¹,

Stone

Griffin

et al. 2010

Biochemistry

Self Cite

View full text Add to dashboard Cite

Guanylyl cyclase A and B (GC-A and GC-B) are transmembrane guanylyl cyclase receptors that mediate the physiologic effects of natriuretic peptides. Some sites of phosphorylation are known for rat GC-A and GC-B, but no phosphorylation site information is available for the human homologs. Here, we used mass spectrometry to identify phosphorylation sites in GC-A and GC-B from both species. Tryptic digests of receptors purified from HEK293 cells were separated and analyzed by nLC-MS-MS. Seven sites of phosphorylation were identified in rat GC-A (S497, T500, S502, S506, S510, T513, and S487) and all of these sites except S510 and T513 were observed in human GC-A. Six phosphorylation sites were identified in rat GC-B (S513, T516, S518, S523, S526, and T529) and all six sites were also identified in human GC-B. Five sites are identical between GC-A and GC-B. S487 in GC-A and T529 in GC-B are novel, uncharacterized sites. Substitution of alanine for S487 did not affect initial ligand-dependent GC-A activity, but a glutamate substitution reduced activity 20%. Similar levels of ANP-dependent desensitization were observed for the wild type, S487A and S487E forms of GC-A. Substitution of glutamate or alanine for T529 increased or decreased ligand-dependent cyclase activity of GC-B, respectively, and T529E increased cyclase activity in a GC-B mutant containing glutamates for all five previously identified sites as well. In conclusion, we identified and characterized new phosphorylation sites in GC-A and GC-B and provide the first evidence of phosphorylation sites within human guanylyl cyclases.

show abstract

“…Exposure to hormones or paracrine factors known to antagonize the actions of GC-B by activating G protein coupled receptors also leads to the dephosphorylation [21,25,43] and inactivation [22, 23, 27, 35, 39, 40, 46, 47] of GC-B in other cell types. However, except for a study of luteinizing hormone action on ovarian follicles [25], these previous studies did not couple changes in GC-B phosphorylation to physiological events.…”

Section: Discussionmentioning

confidence: 99%

“…Early studies showed that activation of several G protein coupled receptors inactivates GC-B, through a process involving dephosphorylation [21, 22]. Recently, luteinizing hormone (LH) was shown to stimulate GC-B dephosphorylation and inactivation in ovarian follicles by a process that requires a PPP family serine and threonine protein phosphatase [23].…”

Section: Introductionmentioning

confidence: 99%

Dephosphorylation is the mechanism of fibroblast growth factor inhibition of guanylyl cyclase-B

Robinson

Egbert

Davydova

et al. 2017

Cellular Signalling

Self Cite

View full text Add to dashboard Cite

Activating mutations in fibroblast growth factor receptor 3 (FGFR3) and inactivating mutations of guanylyl cyclase-B (GC-B, also called NPRB or NPR2) cause dwarfism. FGF exposure inhibits GC-B activity in a chondrocyte cell line, but the mechanism of the inactivation is not known. Here, we report that FGF exposure causes dephosphorylation of GC-B in rat chondrosarcoma cells, which correlates with a rapid, potent and reversible inhibition of C-type natriuretic peptide-dependent activation of GC-B. Cells expressing a phosphomimetic mutant of GC-B that cannot be inactivated by dephosphorylation because it contains glutamate substitutions for all known phosphorylation sites showed no decrease in GC-B activity in response to FGF. We conclude that FGF rapidly inactivates GC-B by a reversible dephosphorylation mechanism, which may contribute to the signaling network by which activated FGFR3 causes dwarfism.

show abstract

Differential regulation of NPR-B/GC-B by protein kinase c and calcium

Cited by 31 publications

References 26 publications

Guanylyl Cyclases A and B Are Asymmetric Dimers That Are Allosterically Activated by ATP Binding to the Catalytic Domain

Guanylyl Cyclases A and B Are Asymmetric Dimers That Are Allosterically Activated by ATP Binding to the Catalytic Domain

Mass Spectrometric Identification of Phosphorylation Sites in Guanylyl Cyclase A and B

Dephosphorylation is the mechanism of fibroblast growth factor inhibition of guanylyl cyclase-B

Contact Info

Product

Resources

About