QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, January 18, 2006, 26(3):1026-1035; doi:10.1523/JNEUROSCI.4258-05.2006

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by Hu, J.-Y. Articles by Schacher, S. Search for Related Content PubMed PubMed Citation Articles by Hu, J.-Y. Articles by Schacher, S. Pubmed/NCBI databases Compound via MeSH Substance via MeSH

 Previous Article  |  Next Article 

Cellular/Molecular
Two Signaling Pathways Regulate the Expression and Secretion of a Neuropeptide Required for Long-Term Facilitation in Aplysia

Jiang-Yuan Hu, Fang Wu, and Samuel Schacher

Center for Neurobiology and Behavior, Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute, New York, New York 10032

Activation of several signaling pathways contributes to long-term synaptic plasticity, but how brief stimuli produce coordinated activation of these pathways is not understood. In Aplysia, the long-term facilitation (LTF) of sensory neuron synapses by 5-hydroxytryptamine (serotonin; 5-HT) requires the activation of several kinases, including mitogen-activated protein kinase (MAPK). The 5-HT-enhanced secretion of the sensory neuron-specific neuropeptide sensorin mediates the activation of MAPK. We find that stimulus-induced activation of two signaling pathways, phosphoinositide 3-kinase (PI3K) and type II protein kinase A (PKA), regulate sensorin secretion and responses. Treatment with 5-HT produces a rapid increase in sensorin synthesis, especially at varicosities, which precedes the secretion of sensorin. PI3K inhibitor and rapamycin block LTF and the rapid synthesis of sensorin at varicosities even in the absence of sensory neuron cell bodies. Secretion of the newly synthesized sensorin from the varicosities and activation of the autocrine responses of sensorin to produce LTF require type II PKA interaction with AKAPs (A-kinase anchoring proteins). Thus, long-term synaptic plasticity is produced when multiple signaling pathways that are important for regulating distinct cellular functions are activated in a specific sequence and recruit the secretion of a neuropeptide to activate additional critical pathways.

Key words: sensorin; PI3K; type II PKA; MAPK; long-term synaptic plasticity; learning and memory; cell culture

---

Received Oct 6, 2005; revised December 5, 2005; accepted December 7, 2005.

This article has been cited by other articles:

				A. Giuditta, J. Tai Chun, M. Eyman, C. Cefaliello, A. P. Bruno, and M. Crispino Local Gene Expression in Axons and Nerve Endings: The Glia-Neuron Unit Physiol Rev, April 1, 2008; 88(2): 515 - 555. [Abstract] [Full Text] [PDF]

				J.-Y. Hu, Y. Chen, and S. Schacher Multifunctional Role of Protein Kinase C in Regulating the Formation and Maturation of Specific Synapses J. Neurosci., October 24, 2007; 27(43): 11712 - 11724. [Abstract] [Full Text] [PDF]

				R. M. S. Weragoda and E. T. Walters Serotonin Induces Memory-Like, Rapamycin-Sensitive Hyperexcitability in Sensory Axons of Aplysia That Contributes to Injury Responses J Neurophysiol, September 1, 2007; 98(3): 1231 - 1239. [Abstract] [Full Text] [PDF]

				J.-Y. Hu, Y. Chen, and S. Schacher Protein Kinase C Regulates Local Synthesis and Secretion of a Neuropeptide Required for Activity-Dependent Long-Term Synaptic Plasticity J. Neurosci., August 15, 2007; 27(33): 8927 - 8939. [Abstract] [Full Text] [PDF]

				P. Lovell and L. L. Moroz The largest growth cones in the animal kingdom: an illustrated guide to the dynamics of Aplysia neuronal growth in cell culture Integr. Comp. Biol., December 1, 2006; 46(6): 847 - 870. [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]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help