The Journal of Neuroscience, July 14, 2004, 24(28):6352-6361; doi:10.1523/JNEUROSCI.0995-04.2004
Previous Article | Next Article 
Cellular/Molecular
Activation of the Phosphoinositide 3-Kinase-Akt-Mammalian Target of Rapamycin Signaling Pathway Is Required for Metabotropic Glutamate Receptor-Dependent Long-Term Depression
Lingfei Hou1 and
Eric Klann1,2
Departments of 1Molecular Physiology and Biophysics and 2Neuroscience, Baylor College of Medicine, Houston, Texas 77030
Hippocampal long-term depression (LTD) is a long-lasting decrease in synaptic strength that is most commonly studied at glutamatergic inputs to pyramidal cells in hippocampal area CA1. Activation of G-protein-coupled group I (including types 1 and 5) metabotropic glutamate receptors (mGluRs) by the pharmacological agonist (RS)-3,5-dihydroxyphenylglycine (DHPG) elicits LTD in area CA1 of the hippocampus. Recent reports have shown that de novo protein synthesis is necessary for DHPG-induced LTD. However, relatively little is known about the signaling pathways that couple mGluRs to translation initiation. In this study, we investigated whether the activation of the phosphoinositide 3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) pathway, which has been shown to regulate translation initiation, is necessary for mGluR-LTD induced by DHPG. We found that brief incubations of mouse hippocampal slices with DHPG resulted in increased phosphorylation of Akt and mTOR in hippocampal area CA1. Two structurally unrelated PI3K inhibitors, LY294002 and wortmannin, blocked the DHPG-induced increases in phosphorylation of Akt and mTOR. Biochemical fractionation studies showed that the DHPG-induced increase in the phosphorylation of Akt and mTOR could be detected in synaptoneurosome preparations, and immunohistochemical analysis revealed that similar increases could be detected in both stratum pyramidale and stratum radiatum in area CA1. Finally, we observed that both PI3K inhibitors and rapamycin, an mTOR inhibitor, prevented mGluR-LTD induced by DHPG. Together, our findings indicate that activation of the PI3K-Akt-mTOR signaling cascade is required for mGluR-LTD and suggest that this pathway may couple group I mGluRs to translation initiation in hippocampal area CA1.
Key words: CA1; hippocampus; phosphorylation; protein kinase; translation initiation; synaptic plasticity
Received March 17, 2004;
accepted May 26, 2004.
This article has been cited by other articles:

|
 |

|
 |
 
S. Piccinin, C. Cinque, L. Calo, G. Molinaro, G. Battaglia, L. Maggi, F. Nicoletti, D. Melchiorri, F. Eusebi, P. V. Massey, et al.
Interaction between Ephrins and mGlu5 Metabotropic Glutamate Receptors in the Induction of Long-Term Synaptic Depression in the Hippocampus
J. Neurosci.,
February 24, 2010;
30(8):
2835 - 2843.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Sharma, C. A. Hoeffer, Y. Takayasu, T. Miyawaki, S. M. McBride, E. Klann, and R. S. Zukin
Dysregulation of mTOR Signaling in Fragile X Syndrome
J. Neurosci.,
January 13, 2010;
30(2):
694 - 702.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
F. M. Ribeiro, M. Paquet, L. T. Ferreira, T. Cregan, P. Swan, S. P. Cregan, and S. S. G. Ferguson
Metabotropic Glutamate Receptor-Mediated Cell Signaling Pathways Are Altered in a Mouse Model of Huntington's Disease
J. Neurosci.,
January 6, 2010;
30(1):
316 - 324.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. M. Gladding, S. M. Fitzjohn, and E. Molnar
Metabotropic Glutamate Receptor-Mediated Long-Term Depression: Molecular Mechanisms
Pharmacol. Rev.,
December 1, 2009;
61(4):
395 - 412.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. C. Ljungberg, C. N. Sunnen, J. N. Lugo, A. E. Anderson, and G. D'Arcangelo
Rapamycin suppresses seizures and neuronal hypertrophy in a mouse model of cortical dysplasia
Dis. Model. Mech.,
July 1, 2009;
2(7-8):
389 - 398.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. S. Buckmaster, E. A. Ingram, and X. Wen
Inhibition of the Mammalian Target of Rapamycin Signaling Pathway Suppresses Dentate Granule Cell Axon Sprouting in a Rodent Model of Temporal Lobe Epilepsy
J. Neurosci.,
June 24, 2009;
29(25):
8259 - 8269.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. R. Ireland and W. C. Abraham
Mechanisms of Group I mGluR-Dependent Long-Term Depression of NMDA Receptor-Mediated Transmission at Schaffer Collateral-CA1 Synapses
J Neurophysiol,
March 1, 2009;
101(3):
1375 - 1385.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. D. Richter and E. Klann
Making synaptic plasticity and memory last: mechanisms of translational regulation
Genes & Dev.,
January 1, 2009;
23(1):
1 - 11.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. Zhang, D. V. Venkitaramani, C. M. Gladding, Y. Zhang, P. Kurup, E. Molnar, G. L. Collingridge, and P. J. Lombroso
The Tyrosine Phosphatase STEP Mediates AMPA Receptor Endocytosis after Metabotropic Glutamate Receptor Stimulation
J. Neurosci.,
October 15, 2008;
28(42):
10561 - 10566.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
U. Narayanan, V. Nalavadi, M. Nakamoto, G. Thomas, S. Ceman, G. J. Bassell, and S. T. Warren
S6K1 Phosphorylates and Regulates Fragile X Mental Retardation Protein (FMRP) with the Neuronal Protein Synthesis-dependent Mammalian Target of Rapamycin (mTOR) Signaling Cascade
J. Biol. Chem.,
July 4, 2008;
283(27):
18478 - 18482.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. R. Moult, S. A. L. Correa, G. L. Collingridge, S. M. Fitzjohn, and Z. I. Bashir
Co-activation of p38 mitogen-activated protein kinase and protein tyrosine phosphatase underlies metabotropic glutamate receptor-dependent long-term depression
J. Physiol.,
May 15, 2008;
586(10):
2499 - 2510.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. D. Antion, L. Hou, H. Wong, C. A. Hoeffer, and E. Klann
mGluR-Dependent Long-Term Depression Is Associated with Increased Phosphorylation of S6 and Synthesis of Elongation Factor 1A but Remains Expressed in S6K-Deficient Mice
Mol. Cell. Biol.,
May 1, 2008;
28(9):
2996 - 3007.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P.-C. Yang, C.-H. Yang, C.-C. Huang, and K.-S. Hsu
Phosphatidylinositol 3-Kinase Activation Is Required for Stress Protocol-induced Modification of Hippocampal Synaptic Plasticity
J. Biol. Chem.,
February 1, 2008;
283(5):
2631 - 2643.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. A. Ronesi and K. M. Huber
Homer Interactions Are Necessary for Metabotropic Glutamate Receptor-Induced Long-Term Depression and Translational Activation
J. Neurosci.,
January 9, 2008;
28(2):
543 - 547.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. D. Antion, M. Merhav, C. A. Hoeffer, G. Reis, S. C. Kozma, G. Thomas, E. M. Schuman, K. Rosenblum, and E. Klann
Removal of S6K1 and S6K2 leads to divergent alterations in learning, memory, and synaptic plasticity
Learn. Mem.,
January 3, 2008;
15(1):
29 - 38.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
N. Chen and J. L. Napoli
All-trans-retinoic acid stimulates translation and induces spine formation in hippocampal neurons through a membrane-associated RAR{alpha}
FASEB J,
January 1, 2008;
22(1):
236 - 245.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. Davidkova and R. C. Carroll
Characterization of the Role of Microtubule-Associated Protein 1B in Metabotropic Glutamate Receptor-Mediated Endocytosis of AMPA Receptors in Hippocampus
J. Neurosci.,
November 28, 2007;
27(48):
13273 - 13278.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Kumar and T. C. Foster
Shift in Induction Mechanisms Underlies an Age-Dependent Increase in DHPG-Induced Synaptic Depression at CA3 CA1 Synapses
J Neurophysiol,
November 1, 2007;
98(5):
2729 - 2736.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. J. Volk, B. E. Pfeiffer, J. R. Gibson, and K. M. Huber
Multiple Gq-Coupled Receptors Converge on a Common Protein Synthesis-Dependent Long-Term Depression That Is Affected in Fragile X Syndrome Mental Retardation
J. Neurosci.,
October 24, 2007;
27(43):
11624 - 11634.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. N. Gelinas, J. L. Banko, L. Hou, N. Sonenberg, E. J. Weeber, E. Klann, and P. V. Nguyen
ERK and mTOR Signaling Couple beta-Adrenergic Receptors to Translation Initiation Machinery to Gate Induction of Protein Synthesis-dependent Long-term Potentiation
J. Biol. Chem.,
September 14, 2007;
282(37):
27527 - 27535.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Mameli, B. Balland, R. Lujan, and C. Luscher
Rapid Synthesis and Synaptic Insertion of GluR2 for mGluR-LTD in the Ventral Tegmental Area
Science,
July 27, 2007;
317(5837):
530 - 533.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
F. Chaouloff, A. Hemar, and O. Manzoni
Acute Stress Facilitates Hippocampal CA1 Metabotropic Glutamate Receptor-Dependent Long-Term Depression
J. Neurosci.,
July 4, 2007;
27(27):
7130 - 7135.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. Tsokas, T. Ma, R. Iyengar, E. M. Landau, and R. D. Blitzer
Mitogen-Activated Protein Kinase Upregulates the Dendritic Translation Machinery in Long-Term Potentiation by Controlling the Mammalian Target of Rapamycin Pathway
J. Neurosci.,
May 30, 2007;
27(22):
5885 - 5894.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Carroll, J. Dyer, and W. S. Sossin
Serotonin Increases Phosphorylation of Synaptic 4EBP through TOR, but Eukaryotic Initiation Factor 4E Levels Do Not Limit Somatic Cap-Dependent Translation in Aplysia Neurons
Mol. Cell. Biol.,
November 15, 2006;
26(22):
8586 - 8598.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. F. Raab-Graham, P. C. G. Haddick, Y. N. Jan, and L. Y. Jan
Activity- and mTOR-dependent suppression of Kv1.1 channel mRNA translation in dendrites.
Science,
October 6, 2006;
314(5796):
144 - 148.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. Silverman-Gavrila and R. Silverman-Gavrila
Depression in the Fly
J. Neurosci.,
August 2, 2006;
26(31):
8021 - 8022.
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. Gong, C. S. Park, N. R. Abbassi, and S.-J. Tang
Roles of Glutamate Receptors and the Mammalian Target of Rapamycin (mTOR) Signaling Pathway in Activity-dependent Dendritic Protein Synthesis in Hippocampal Neurons
J. Biol. Chem.,
July 7, 2006;
281(27):
18802 - 18815.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. E. Pfeiffer and K. M. Huber
Current advances in local protein synthesis and synaptic plasticity.
J. Neurosci.,
July 5, 2006;
26(27):
7147 - 7150.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
W. Zhang and D. J. Linden
Long-term depression at the mossy fiber-deep cerebellar nucleus synapse.
J. Neurosci.,
June 28, 2006;
26(26):
6935 - 6944.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. J. O'Riordan, I-C. Huang, M. Pizzi, P. Spano, F. Boroni, R. Egli, P. Desai, O. Fitch, L. Malone, H. Jin Ahn, et al.
Regulation of nuclear factor kappaB in the hippocampus by group I metabotropic glutamate receptors.
J. Neurosci.,
May 3, 2006;
26(18):
4870 - 4879.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H.-F. Guo and Y. Zhong
Requirement of Akt to Mediate Long-Term Synaptic Depression in Drosophila
J. Neurosci.,
April 12, 2006;
26(15):
4004 - 4014.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. J. Volk, C. A. Daly, and K. M. Huber
Differential Roles for Group 1 mGluR Subtypes in Induction and Expression of Chemically Induced Hippocampal Long-Term Depression
J Neurophysiol,
April 1, 2006;
95(4):
2427 - 2438.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. L. Banko, L. Hou, F. Poulin, N. Sonenberg, and E. Klann
Regulation of eukaryotic initiation factor 4E by converging signaling pathways during metabotropic glutamate receptor-dependent long-term depression.
J. Neurosci.,
February 22, 2006;
26(8):
2167 - 2173.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. Jaworski, S. Spangler, D. P. Seeburg, C. C. Hoogenraad, and M. Sheng
Control of Dendritic Arborization by the Phosphoinositide-3'-Kinase-Akt-Mammalian Target of Rapamycin Pathway
J. Neurosci.,
December 7, 2005;
25(49):
11300 - 11312.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S.-C. Chuang, W. Zhao, R. Bauchwitz, Q. Yan, R. Bianchi, and R. K. S. Wong
Prolonged Epileptiform Discharges Induced by Altered Group I Metabotropic Glutamate Receptor-Mediated Synaptic Responses in Hippocampal Slices of a Fragile X Mouse Model
J. Neurosci.,
August 31, 2005;
25(35):
8048 - 8055.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. Tsokas, E. A. Grace, P. Chan, T. Ma, S. C. Sealfon, R. Iyengar, E. M. Landau, and R. D. Blitzer
Local Protein Synthesis Mediates a Rapid Increase in Dendritic Elongation Factor 1A after Induction of Late Long-Term Potentiation
J. Neurosci.,
June 15, 2005;
25(24):
5833 - 5843.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. Mutoh, Q. Yuan, and T. Knopfel
Long-Term Depression at Olfactory Nerve Synapses
J. Neurosci.,
April 27, 2005;
25(17):
4252 - 4259.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. Klann, M. D. Antion, J. L. Banko, and L. Hou
Synaptic Plasticity and Translation Initiation
Learn. Mem.,
July 1, 2004;
11(4):
365 - 372.
[Abstract]
[Full Text]
[PDF]
|
 |
|