Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel NaV1.2 in neurons
Neuronal ankyrin-B is an intracellular scaffolding protein that plays multiple roles in the axon. By contrast, relatively little is known about the function of ankyrin-B in dendrites, where ankyrin-B is also localized in mature neurons. Recently, we showed that ankyrin-B acts as a scaffold for the v...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2023-03-01
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| Series: | Frontiers in Physiology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fphys.2023.959660/full |
| _version_ | 1797856265869721600 |
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| author | Julie P. Gupta Paul M. Jenkins Paul M. Jenkins |
| author_facet | Julie P. Gupta Paul M. Jenkins Paul M. Jenkins |
| author_sort | Julie P. Gupta |
| collection | DOAJ |
| description | Neuronal ankyrin-B is an intracellular scaffolding protein that plays multiple roles in the axon. By contrast, relatively little is known about the function of ankyrin-B in dendrites, where ankyrin-B is also localized in mature neurons. Recently, we showed that ankyrin-B acts as a scaffold for the voltage-gated sodium channel, NaV1.2, in dendrites of neocortical pyramidal neurons. How ankyrin-B is itself targeted to the dendritic membrane is not well understood. Here, we report that ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic localization of NaV1.2. We identify the palmitoyl acyl transferase zDHHC17 as a key mediator of ankyrin-B palmitoylation in heterologous cells and in neurons. Additionally, we find that zDHHC17 regulates ankyrin-B protein levels independently of its S-acylation function through a conserved binding mechanism between the ANK repeat domain of zDHHC17 and the zDHHC ankyrin-repeat binding motif of ankyrin-B. We subsequently identify five cysteines in the N-terminal ankyrin repeat domain of ankyrin-B that are necessary for ankyrin-B palmitoylation. Mutation of these five cysteines to alanines not only abolishes ankyrin-B palmitoylation, but also prevents ankyrin-B from scaffolding NaV1.2 at dendritic membranes of neurons due to ankyrin-B’s inability to localize properly at dendrites. Thus, we show palmitoylation is critical for localization and function of ankyrin-B at dendrites. Strikingly, loss of ankyrin-B palmitoylation does not affect ankyrin-B-mediated axonal cargo transport of synaptic vesicle synaptotagmin-1 in neurons. This is the first demonstration of S-palmitoylation of ankyrin-B as an underlying mechanism required for ankyrin-B localization and function in scaffolding NaV1.2 at dendrites. |
| first_indexed | 2024-04-09T20:37:38Z |
| format | Article |
| id | doaj.art-28a93bfee2184493977172c2fb36da4e |
| institution | Directory Open Access Journal |
| issn | 1664-042X |
| language | English |
| last_indexed | 2024-04-09T20:37:38Z |
| publishDate | 2023-03-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Physiology |
| spelling | doaj.art-28a93bfee2184493977172c2fb36da4e2023-03-30T07:00:58ZengFrontiers Media S.A.Frontiers in Physiology1664-042X2023-03-011410.3389/fphys.2023.959660959660Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel NaV1.2 in neuronsJulie P. Gupta0Paul M. Jenkins1Paul M. Jenkins2Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, United StatesDepartment of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, United StatesDepartment of Psychiatry, University of Michigan Medical School, Ann Arbor, MI, United StatesNeuronal ankyrin-B is an intracellular scaffolding protein that plays multiple roles in the axon. By contrast, relatively little is known about the function of ankyrin-B in dendrites, where ankyrin-B is also localized in mature neurons. Recently, we showed that ankyrin-B acts as a scaffold for the voltage-gated sodium channel, NaV1.2, in dendrites of neocortical pyramidal neurons. How ankyrin-B is itself targeted to the dendritic membrane is not well understood. Here, we report that ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic localization of NaV1.2. We identify the palmitoyl acyl transferase zDHHC17 as a key mediator of ankyrin-B palmitoylation in heterologous cells and in neurons. Additionally, we find that zDHHC17 regulates ankyrin-B protein levels independently of its S-acylation function through a conserved binding mechanism between the ANK repeat domain of zDHHC17 and the zDHHC ankyrin-repeat binding motif of ankyrin-B. We subsequently identify five cysteines in the N-terminal ankyrin repeat domain of ankyrin-B that are necessary for ankyrin-B palmitoylation. Mutation of these five cysteines to alanines not only abolishes ankyrin-B palmitoylation, but also prevents ankyrin-B from scaffolding NaV1.2 at dendritic membranes of neurons due to ankyrin-B’s inability to localize properly at dendrites. Thus, we show palmitoylation is critical for localization and function of ankyrin-B at dendrites. Strikingly, loss of ankyrin-B palmitoylation does not affect ankyrin-B-mediated axonal cargo transport of synaptic vesicle synaptotagmin-1 in neurons. This is the first demonstration of S-palmitoylation of ankyrin-B as an underlying mechanism required for ankyrin-B localization and function in scaffolding NaV1.2 at dendrites.https://www.frontiersin.org/articles/10.3389/fphys.2023.959660/fullAnkyrin-Bpost-translational modificationS-palmitoylationzDHHC enzymeslocalizationscaffolding |
| spellingShingle | Julie P. Gupta Paul M. Jenkins Paul M. Jenkins Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel NaV1.2 in neurons Frontiers in Physiology Ankyrin-B post-translational modification S-palmitoylation zDHHC enzymes localization scaffolding |
| title | Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel NaV1.2 in neurons |
| title_full | Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel NaV1.2 in neurons |
| title_fullStr | Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel NaV1.2 in neurons |
| title_full_unstemmed | Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel NaV1.2 in neurons |
| title_short | Ankyrin-B is lipid-modified by S-palmitoylation to promote dendritic membrane scaffolding of voltage-gated sodium channel NaV1.2 in neurons |
| title_sort | ankyrin b is lipid modified by s palmitoylation to promote dendritic membrane scaffolding of voltage gated sodium channel nav1 2 in neurons |
| topic | Ankyrin-B post-translational modification S-palmitoylation zDHHC enzymes localization scaffolding |
| url | https://www.frontiersin.org/articles/10.3389/fphys.2023.959660/full |
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