Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity
Maintenance of neural circuit activity requires appropriate regulation of excitatory and inhibitory synaptic transmission. Recently, glia have emerged as key partners in the modulation of neuronal excitability; however, the mechanisms by which glia regulate neuronal signaling are still being elucida...
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| Format: | Article |
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Society for Neuroscience
2018
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| Online Access: | http://hdl.handle.net/1721.1/117351 https://orcid.org/0000-0001-7463-977X https://orcid.org/0000-0001-5576-2887 |
| _version_ | 1811097969465753600 |
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| author | Zhang, Yao Ormerod, Kiel G Littleton, J. Troy |
| author2 | Massachusetts Institute of Technology. Department of Biology |
| author_facet | Massachusetts Institute of Technology. Department of Biology Zhang, Yao Ormerod, Kiel G Littleton, J. Troy |
| author_sort | Zhang, Yao |
| collection | MIT |
| description | Maintenance of neural circuit activity requires appropriate regulation of excitatory and inhibitory synaptic transmission. Recently, glia have emerged as key partners in the modulation of neuronal excitability; however, the mechanisms by which glia regulate neuronal signaling are still being elucidated. Here, we describe an analysis of how Ca[superscript 2+] signals within Drosophila astrocyte-like glia regulate excitability in the nervous system. We find that Drosophila astrocytes exhibit robust Ca[superscript 2+] oscillatory activity manifested by fast, recurrent microdomain Ca[superscript 2+] fluctuations within processes that infiltrate the synaptic neuropil. Unlike the enhanced neuronal activity and behavioral seizures that were previously observed during manipulations that trigger Ca[superscript 2+] influx into Drosophila cortex glia, we find that acute induction of astrocyte Ca[superscript 2+] influx leads to a rapid onset of behavioral paralysis and a suppression of neuronal activity. We observe that Ca[superscript 2+] influx triggers rapid endocytosis of the GABA transporter (GAT) from astrocyte plasma membranes, suggesting that increased synaptic GABA levels contribute to the neuronal silencing and paralysis. We identify Rab11 as a novel regulator of GAT trafficking that is required for this form of activity regulation. Suppression of Rab11 function strongly offsets the reduction of neuronal activity caused by acute astrocyte Ca[superscript 2+] influx, likely by inhibiting GAT endocytosis. Our data provide new insights into astrocyte Ca[superscript 2+] signaling and indicate that distinct glial subtypes in the Drosophila brain can mediate opposing effects on neuronal excitability. Keywords: astrocyte; Ca[superscript 2+]; Drosophila; GABA; GAT; Rab11 |
| first_indexed | 2024-09-23T17:07:52Z |
| format | Article |
| id | mit-1721.1/117351 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T17:07:52Z |
| publishDate | 2018 |
| publisher | Society for Neuroscience |
| record_format | dspace |
| spelling | mit-1721.1/1173512022-09-29T23:53:31Z Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity Zhang, Yao Ormerod, Kiel G Littleton, J. Troy Massachusetts Institute of Technology. Department of Biology Picower Institute for Learning and Memory Zhang, Yao Ormerod, Kiel G Littleton, J. Troy Maintenance of neural circuit activity requires appropriate regulation of excitatory and inhibitory synaptic transmission. Recently, glia have emerged as key partners in the modulation of neuronal excitability; however, the mechanisms by which glia regulate neuronal signaling are still being elucidated. Here, we describe an analysis of how Ca[superscript 2+] signals within Drosophila astrocyte-like glia regulate excitability in the nervous system. We find that Drosophila astrocytes exhibit robust Ca[superscript 2+] oscillatory activity manifested by fast, recurrent microdomain Ca[superscript 2+] fluctuations within processes that infiltrate the synaptic neuropil. Unlike the enhanced neuronal activity and behavioral seizures that were previously observed during manipulations that trigger Ca[superscript 2+] influx into Drosophila cortex glia, we find that acute induction of astrocyte Ca[superscript 2+] influx leads to a rapid onset of behavioral paralysis and a suppression of neuronal activity. We observe that Ca[superscript 2+] influx triggers rapid endocytosis of the GABA transporter (GAT) from astrocyte plasma membranes, suggesting that increased synaptic GABA levels contribute to the neuronal silencing and paralysis. We identify Rab11 as a novel regulator of GAT trafficking that is required for this form of activity regulation. Suppression of Rab11 function strongly offsets the reduction of neuronal activity caused by acute astrocyte Ca[superscript 2+] influx, likely by inhibiting GAT endocytosis. Our data provide new insights into astrocyte Ca[superscript 2+] signaling and indicate that distinct glial subtypes in the Drosophila brain can mediate opposing effects on neuronal excitability. Keywords: astrocyte; Ca[superscript 2+]; Drosophila; GABA; GAT; Rab11 2018-08-14T13:25:50Z 2018-08-14T13:25:50Z 2017-03 2016-11 2018-08-13T13:18:24Z Article http://purl.org/eprint/type/JournalArticle 2373-2822 http://hdl.handle.net/1721.1/117351 Zhang, Yao V., et al. “Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity.” Eneuro, vol. 4, no. 2, 2017, p. ENEURO.0340-16.2017. © 2017 Zhang et al. https://orcid.org/0000-0001-7463-977X https://orcid.org/0000-0001-5576-2887 http://dx.doi.org/10.1523/ENEURO.0340-16.2017 eneuro Creative Commons Attribution 4.0 International License http://creativecommons.org/licenses/by/4.0/ application/pdf Society for Neuroscience Society for Neuroscience |
| spellingShingle | Zhang, Yao Ormerod, Kiel G Littleton, J. Troy Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity |
| title | Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity |
| title_full | Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity |
| title_fullStr | Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity |
| title_full_unstemmed | Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity |
| title_short | Astrocyte Ca[superscript 2+] Influx Negatively Regulates Neuronal Activity |
| title_sort | astrocyte ca superscript 2 influx negatively regulates neuronal activity |
| url | http://hdl.handle.net/1721.1/117351 https://orcid.org/0000-0001-7463-977X https://orcid.org/0000-0001-5576-2887 |
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