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Andresen H, Pérez‐Ternero C, Robinson J, Dickey DM, Hobbs AJ, Potter LR, Levy FO, Cataliotti A, Moltzau LR. Novel enhancers of guanylyl cyclase-A activity acting via allosteric modulation. Br J Pharmacol 2023; 180:3254-3270. [PMID: 37522273 PMCID: PMC10952227 DOI: 10.1111/bph.16203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 06/30/2023] [Accepted: 07/11/2023] [Indexed: 08/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Guanylyl cyclase-A (GC-A), activated by endogenous atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), plays an important role in the regulation of cardiovascular and renal homeostasis and is an attractive drug target. Even though small molecule modulators allow oral administration and longer half-life, drug targeting of GC-A has so far been limited to peptides. Thus, in this study we aimed to develop small molecular activators of GC-A. EXPERIMENTAL APPROACH Hits were identified through high-throughput screening and optimized by in silico design. Cyclic GMP was measured in QBIHEK293A cells expressing GC-A, GC-B or chimerae of the two receptors using AlphaScreen technology. Binding assays were performed in membrane preparations or whole cells using 125 I-ANP. Vasorelaxation was measured in aortic rings isolated from Wistar rats. KEY RESULTS We have identified small molecular allosteric enhancers of GC-A, which enhanced ANP or BNP effects in cellular systems and ANP-induced vasorelaxation in rat aortic rings. The mechanism of action appears novel and not mediated through previously described allosteric binding sites. In addition, the selectivity and activity depend on a single amino acid residue that differs between the two similar receptors GC-A and GC-B. CONCLUSION AND IMPLICATIONS We describe a novel allosteric binding site on GC-A, which can be targeted by small molecules to enhance ANP and BNP effects. These compounds will be valuable tools in further development and proof-of-concept of GC-A enhancement for the potential use in cardiovascular therapy.
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Affiliation(s)
- Henriette Andresen
- Department of Pharmacology, Institute of Clinical MedicineUniversity of Oslo and Oslo University HospitalOsloNorway
- Institute for Experimental Medical ResearchUniversity of Oslo and Oslo University HospitalOsloNorway
| | - Cristina Pérez‐Ternero
- William Harvey Research Institute, Barts & The London School of Medicine and DentistryQueen Mary University of LondonLondonUK
| | - Jerid Robinson
- Department of Biochemistry, Molecular Biology, and BiophysicsUniversity of Minnesota Medical SchoolMinneapolisMinnesotaUSA
| | - Deborah M. Dickey
- Department of Biochemistry, Molecular Biology, and BiophysicsUniversity of Minnesota Medical SchoolMinneapolisMinnesotaUSA
| | - Adrian J. Hobbs
- William Harvey Research Institute, Barts & The London School of Medicine and DentistryQueen Mary University of LondonLondonUK
| | - Lincoln R. Potter
- Department of Biochemistry, Molecular Biology, and BiophysicsUniversity of Minnesota Medical SchoolMinneapolisMinnesotaUSA
| | - Finn Olav Levy
- Department of Pharmacology, Institute of Clinical MedicineUniversity of Oslo and Oslo University HospitalOsloNorway
| | - Alessandro Cataliotti
- Institute for Experimental Medical ResearchUniversity of Oslo and Oslo University HospitalOsloNorway
| | - Lise Román Moltzau
- Department of Pharmacology, Institute of Clinical MedicineUniversity of Oslo and Oslo University HospitalOsloNorway
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Xi G, An L, Jia Z, Tan K, Zhang J, Wang Z, Zhang C, Miao K, Wu Z, Tian J. Natriuretic peptide receptor 2 (NPR2) localized in bovine oocyte underlies a unique mechanism for C-type natriuretic peptide (CNP)-induced meiotic arrest. Theriogenology 2017; 106:198-209. [PMID: 29080478 DOI: 10.1016/j.theriogenology.2017.09.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 09/01/2017] [Accepted: 09/02/2017] [Indexed: 01/13/2023]
Abstract
Meiosis is of prime importance for successful gametogenesis, and insufficient maintenance of oocyte meiotic arrest compromises oocyte developmental competence. Recent studies have demonstrated that the C-type natriuretic peptide (CNP)-Natriuretic peptide receptor 2 (NPR2) pathway can inhibit mammalian oocyte meiotic resumption. In mouse and porcine, the inhibitory effect of mural granulosa cell (MGC)-derived CNP on oocyte meiotic resumption is mediated by NPR2 localized in cumulus cells (CCs) surrounding the oocytes. However, in the present study, we identified a novel mechanism for CNP-induced meiotic arrest that appears to be unique to bovine oocytes. Unlike mouse and porcine, bovine NPR2 not only localizes in CCs, but also in oocyte membranes. We also showed that CNP can directly activate intra-oocyte cGMP production via NPR2 localized in oocyte membranes, in parallel with the CC-mediated pathway. Furthermore, we demonstrated that Npr2 expression in bovine CCs and oocytes were synergistically regulated by estradiol and oocyte-derived growth factors. Finally, based on the profound inhibitory effect of CNP on meiotic resumption, we established a natural factor synchronized in vitro oocyte maturation (NFSOM) system, which can significantly improve the developmental competence of matured oocytes, thereby resulting in higher in vitro embryo production efficiency. Taken together, our study not only provides new insight into understanding the crosstalk between oocytes and follicular somatic cells in mammals, but also presents a promising strategy for improving the in vitro oocyte maturation systems of assisted reproductive technology (ART).
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Affiliation(s)
- Guangyin Xi
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China
| | - Lei An
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China
| | - Zhenwei Jia
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China; College of Animal Science and Technology, Inner Mongolia University for the Nationalities, Inner Mongolia 028000, China
| | - Kun Tan
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China
| | - Jiaxin Zhang
- Key Laboratory of Animal Genetics, Breeding and Reproduction, College of Animal Science and Technology, Inner Mongolia Agriculture University, Inner Mongolia 010018, China
| | - Zhuqing Wang
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China
| | - Chao Zhang
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China
| | - Kai Miao
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China
| | - Zhonghong Wu
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China
| | - Jianhui Tian
- National Engineering Laboratory for Animal Breeding, College of Animal Sciences and Technology, China Agricultural University, Beijing 100193, China.
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3
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Dickey DM, Edmund AB, Otto NM, Chaffee TS, Robinson JW, Potter LR. Catalytically Active Guanylyl Cyclase B Requires Endoplasmic Reticulum-mediated Glycosylation, and Mutations That Inhibit This Process Cause Dwarfism. J Biol Chem 2016; 291:11385-93. [PMID: 26980729 DOI: 10.1074/jbc.m115.704015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Indexed: 01/18/2023] Open
Abstract
C-type natriuretic peptide activation of guanylyl cyclase B (GC-B), also known as natriuretic peptide receptor B or NPR2, stimulates long bone growth, and missense mutations in GC-B cause dwarfism. Four such mutants (L658F, Y708C, R776W, and G959A) bound (125)I-C-type natriuretic peptide on the surface of cells but failed to synthesize cGMP in membrane GC assays. Immunofluorescence microscopy also indicated that the mutant receptors were on the cell surface. All mutant proteins were dephosphorylated and incompletely glycosylated, but dephosphorylation did not explain the inactivation because the mutations inactivated a "constitutively phosphorylated" enzyme. Tunicamycin inhibition of glycosylation in the endoplasmic reticulum or mutation of the Asn-24 glycosylation site decreased GC activity, but neither inhibition of glycosylation in the Golgi by N-acetylglucosaminyltransferase I gene inactivation nor PNGase F deglycosylation of fully processed GC-B reduced GC activity. We conclude that endoplasmic reticulum-mediated glycosylation is required for the formation of an active catalytic, but not ligand-binding domain, and that mutations that inhibit this process cause dwarfism.
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Affiliation(s)
- Deborah M Dickey
- From the Departments of Biochemistry, Molecular Biology, and Biophysics and
| | - Aaron B Edmund
- From the Departments of Biochemistry, Molecular Biology, and Biophysics and
| | - Neil M Otto
- From the Departments of Biochemistry, Molecular Biology, and Biophysics and
| | - Thomas S Chaffee
- From the Departments of Biochemistry, Molecular Biology, and Biophysics and
| | - Jerid W Robinson
- From the Departments of Biochemistry, Molecular Biology, and Biophysics and
| | - Lincoln R Potter
- From the Departments of Biochemistry, Molecular Biology, and Biophysics and Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455
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4
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Dephosphorylation of juxtamembrane serines and threonines of the NPR2 guanylyl cyclase is required for rapid resumption of oocyte meiosis in response to luteinizing hormone. Dev Biol 2015; 409:194-201. [PMID: 26522847 DOI: 10.1016/j.ydbio.2015.10.025] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 10/15/2015] [Accepted: 10/20/2015] [Indexed: 01/14/2023]
Abstract
The meiotic cell cycle of mammalian oocytes starts during embryogenesis and then pauses until luteinizing hormone (LH) acts on the granulosa cells of the follicle surrounding the oocyte to restart the cell cycle. An essential event in this process is a decrease in cyclic GMP in the granulosa cells, and part of the cGMP decrease results from dephosphorylation and inactivation of the natriuretic peptide receptor 2 (NPR2) guanylyl cyclase, also known as guanylyl cyclase B. However, it is unknown whether NPR2 dephosphorylation is essential for LH-induced meiotic resumption. Here, we prevented NPR2 dephosphorylation by generating a mouse line in which the seven regulatory serines and threonines of NPR2 were changed to the phosphomimetic amino acid glutamate (Npr2-7E). Npr2-7E/7E follicles failed to show a decrease in enzyme activity in response to LH, and the cGMP decrease was attenuated; correspondingly, LH-induced meiotic resumption was delayed. Meiotic resumption in response to EGF receptor activation was likewise delayed, indicating that NPR2 dephosphorylation is a component of the pathway by which EGF receptor activation mediates LH signaling. We also found that most of the NPR2 protein in the follicle was present in the mural granulosa cells. These findings indicate that NPR2 dephosphorylation in the mural granulosa cells is essential for the normal progression of meiosis in response to LH and EGF receptor activation. In addition, these studies provide the first demonstration that a change in phosphorylation of a transmembrane guanylyl cyclase regulates a physiological process, a mechanism that may also control other developmental events.
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Wang SR, Jacobsen CM, Carmichael H, Edmund AB, Robinson JW, Olney RC, Miller TC, Moon JE, Mericq V, Potter LR, Warman ML, Hirschhorn JN, Dauber A. Heterozygous mutations in natriuretic peptide receptor-B (NPR2) gene as a cause of short stature. Hum Mutat 2015; 36:474-81. [PMID: 25703509 DOI: 10.1002/humu.22773] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 02/09/2015] [Indexed: 12/18/2022]
Abstract
Based on the observation of reduced stature in relatives of patients with acromesomelic dysplasia, Maroteaux type (AMDM), caused by homozygous or compound heterozygous mutations in natriuretic peptide receptor-B gene (NPR2), it has been suggested that heterozygous mutations in this gene could be responsible for the growth impairment observed in some cases of idiopathic short stature (ISS). We enrolled 192 unrelated patients with short stature and 192 controls of normal height and identified seven heterozygous NPR2 missense or splice site mutations all in the short stature patients, including one de novo splice site variant. Three of the six inherited variants segregated with short stature in the family. Nine additional rare nonsynonymous NPR2 variants were found in three additional cohorts. Functional studies identified eight loss-of-function mutations in short individuals and one gain-of-function mutation in tall individuals. With these data, we were able to rigorously verify that NPR2 functional haploinsufficiency contributes to short stature. We estimate a prevalence of NPR2 haploinsufficiency of between 0 and 1/26 in people with ISS. We suggest that NPR2 gain of function may be a more common cause of tall stature than previously recognized.
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Egbert JR, Shuhaibar LC, Edmund AB, Van Helden DA, Robinson JW, Uliasz TF, Baena V, Geerts A, Wunder F, Potter LR, Jaffe LA. Dephosphorylation and inactivation of NPR2 guanylyl cyclase in granulosa cells contributes to the LH-induced decrease in cGMP that causes resumption of meiosis in rat oocytes. Development 2014; 141:3594-604. [PMID: 25183874 DOI: 10.1242/dev.112219] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In mammals, the meiotic cell cycle of oocytes starts during embryogenesis and then pauses. Much later, in preparation for fertilization, oocytes within preovulatory follicles resume meiosis in response to luteinizing hormone (LH). Before LH stimulation, the arrest is maintained by diffusion of cyclic (c)GMP into the oocyte from the surrounding granulosa cells, where it is produced by the guanylyl cyclase natriuretic peptide receptor 2 (NPR2). LH rapidly reduces the production of cGMP, but how this occurs is unknown. Here, using rat follicles, we show that within 10 min, LH signaling causes dephosphorylation and inactivation of NPR2 through a process that requires the activity of phosphoprotein phosphatase (PPP)-family members. The rapid dephosphorylation of NPR2 is accompanied by a rapid phosphorylation of the cGMP phosphodiesterase PDE5, an enzyme whose activity is increased upon phosphorylation. Later, levels of the NPR2 agonist C-type natriuretic peptide decrease in the follicle, and these sequential events contribute to the decrease in cGMP that causes meiosis to resume in the oocyte.
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Affiliation(s)
- Jeremy R Egbert
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Leia C Shuhaibar
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Aaron B Edmund
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Dusty A Van Helden
- Department of Pharmacology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jerid W Robinson
- Department of Pharmacology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tracy F Uliasz
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Valentina Baena
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Andreas Geerts
- Bayer Pharma AG, Pharma Research Center, Wuppertal D-42096, Germany
| | - Frank Wunder
- Bayer Pharma AG, Pharma Research Center, Wuppertal D-42096, Germany
| | - Lincoln R Potter
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA Department of Pharmacology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Laurinda A Jaffe
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
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7
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Robinson JW, Dickey DM, Miura K, Michigami T, Ozono K, Potter LR. A human skeletal overgrowth mutation increases maximal velocity and blocks desensitization of guanylyl cyclase-B. Bone 2013; 56:375-82. [PMID: 23827346 PMCID: PMC4413012 DOI: 10.1016/j.bone.2013.06.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 06/12/2013] [Accepted: 06/24/2013] [Indexed: 01/12/2023]
Abstract
C-type natriuretic peptide (CNP) increases long bone growth by stimulating guanylyl cyclase (GC)-B/NPR-B/NPR2. Recently, a Val to Met missense mutation at position 883 in the catalytic domain of GC-B was identified in humans with increased blood cGMP levels that cause abnormally long bones. Here, we determined how this mutation activates GC-B. In the absence of CNP, cGMP levels in cells expressing V883M-GC-B were increased more than 20 fold compared to cells expressing wild-type (WT)-GC-B, and the addition of CNP only further increased cGMP levels 2-fold. In the absence of CNP, maximal enzymatic activity (Vmax) of V883M-GC-B was increased 15-fold compared to WT-GC-B but the affinity of the enzymes for substrate as revealed by the Michaelis constant (Km) was unaffected. Surprisingly, CNP decreased the Km of V883M-GC-B 10-fold in a concentration-dependent manner without increasing Vmax. Unlike the WT enzyme the Km reduction of V883M-GC-B did not require ATP. Unexpectedly, V883M-GC-B, but not WT-GC-B, failed to inactivate with time. Phosphorylation elevated but was not required for the activity increase associated with the mutation because the Val to Met substitution also activated a GC-B mutant lacking all known phosphorylation sites. We conclude that the V883M mutation increases maximal velocity in the absence of CNP, eliminates the requirement for ATP in the CNP-dependent Km reduction, and disrupts the normal inactivation process.
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Affiliation(s)
- Jerid W. Robinson
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, USA
| | - Deborah M. Dickey
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Kohji Miura
- Department of Pediatrics, Osaka Graduate School of Medicine, Osaka, Japan
| | - Toshimi Michigami
- Department of Bone and Mineral Research, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka Graduate School of Medicine, Osaka, Japan
| | - Lincoln R. Potter
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
- Corresponding author at: University of Minnesota — Twin Cities, 6-155 Jackson Hall, 321 Church St. SE, Minneapolis, MN 55455, USA. Fax: +1 612 624 7282. (L.R. Potter)
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8
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Robinson JW, Potter LR. Guanylyl cyclases A and B are asymmetric dimers that are allosterically activated by ATP binding to the catalytic domain. Sci Signal 2012; 5:ra65. [PMID: 22949736 DOI: 10.1126/scisignal.2003253] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
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 expected for symmetric catalytic dimers. 2'-Deoxy-ATP and 2'-deoxy-GTP were poor allosteric 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.
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Affiliation(s)
- Jerid W Robinson
- Department of Pharmacology, University of Minnesota, Minneapolis, MN 55455, USA
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Yoder AR, Robinson JW, Dickey DM, Andersland J, Rose BA, Stone MD, Griffin TJ, Potter LR. A functional screen provides evidence for a conserved, regulatory, juxtamembrane phosphorylation site in guanylyl cyclase a and B. PLoS One 2012; 7:e36747. [PMID: 22590601 PMCID: PMC3348905 DOI: 10.1371/journal.pone.0036747] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 04/10/2012] [Indexed: 01/10/2023] Open
Abstract
Kinase homology domain (KHD) phosphorylation is required for activation of guanylyl cyclase (GC)-A and -B. Phosphopeptide mapping identified multiple phosphorylation sites in GC-A and GC-B, but these approaches have difficulty identifying sites in poorly detected peptides. Here, a functional screen was conducted to identify novel sites. Conserved serines or threonines in the KHDs of phosphorylated receptor GCs were mutated to alanine and tested for reduced hormone to detergent activity ratios. Mutation of Ser-489 in GC-B to alanine but not glutamate reduced the activity ratio to 60% of wild type (WT) levels. Similar results were observed with Ser-473, the homologous site in GC-A. Receptors containing glutamates for previously identified phosphorylation sites (GC-A-6E and GC-B-6E) were activated to ∼20% of WT levels but the additional glutamate substitution for S473 or S489 increased activity to near WT levels. Substrate-velocity assays indicated that GC-B-WT-S489E and GC-B-6E-S489E had lower Km values and that WT-GC-B-S489A, GC-B-6E and GC-B-6E-S489A had higher Km values than WT-GC-B. Homologous desensitization was enhanced when GC-A contained the S473E substitution, and GC-B-6E-S489E was resistant to inhibition by a calcium elevating treatment or protein kinase C activation – processes that dephosphorylate GC-B. Mass spectrometric detection of a synthetic phospho-Ser-473 containing peptide was 200–1300-fold less sensitive than other phosphorylated peptides and neither mass spectrometric nor 32PO4 co-migration studies detected phospho-Ser-473 or phospho-Ser-489 in cells. We conclude that Ser-473 and Ser-489 are Km-regulating phosphorylation sites that are difficult to detect using current methods.
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Affiliation(s)
- Andrea R. Yoder
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Jerid W. Robinson
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Deborah M. Dickey
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Joshua Andersland
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Beth A. Rose
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Matthew D. Stone
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Timothy J. Griffin
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Lincoln R. Potter
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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10
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Robinson JW, Zhang M, Shuhaibar LC, Norris RP, Geerts A, Wunder F, Eppig JJ, Potter LR, Jaffe LA. Luteinizing hormone reduces the activity of the NPR2 guanylyl cyclase in mouse ovarian follicles, contributing to the cyclic GMP decrease that promotes resumption of meiosis in oocytes. Dev Biol 2012; 366:308-16. [PMID: 22546688 DOI: 10.1016/j.ydbio.2012.04.019] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 03/30/2012] [Accepted: 04/12/2012] [Indexed: 12/23/2022]
Abstract
In preovulatory ovarian follicles of mice, meiotic prophase arrest in the oocyte is maintained by cyclic GMP from the surrounding granulosa cells that diffuses into the oocyte through gap junctions. The cGMP is synthesized in the granulosa cells by the transmembrane guanylyl cyclase natriuretic peptide receptor 2 (NPR2) in response to the agonist C-type natriuretic peptide (CNP). In response to luteinizing hormone (LH), cGMP in the granulosa cells decreases, and as a consequence, oocyte cGMP decreases and meiosis resumes. Here we report that within 20 min, LH treatment results in decreased guanylyl cyclase activity of NPR2, as determined in the presence of a maximally activating concentration of CNP. This occurs by a process that does not reduce the amount of NPR2 protein. We also show that by a slower process, first detected at 2h, LH decreases the amount of CNP available to bind to the receptor. Both of these LH actions contribute to decreasing cGMP in the follicle, thus signaling meiotic resumption in the oocyte.
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Affiliation(s)
- Jerid W Robinson
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, USA.
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