RIBEYE B-Domain Is Essential for RIBEYE A-Domain Stability and Assembly of Synaptic Ribbons

Synaptic ribbons are presynaptic specializations that define eponymous ribbon synapses. Synaptic ribbons are largely composed of RIBEYE, a protein containing an N-terminal A-domain and a carboxyterminal B-domain that is identical with CtBP2, a NAD(H)-binding transcriptional co-repressor. Previously...

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Autores principales: Shankhwar, Soni, Schwarz, Karin, Katiyar, Rashmi, Jung, Martin, Maxeiner, Stephan, Südhof, Thomas C., Schmitz, Frank
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8831697/
https://www.ncbi.nlm.nih.gov/pubmed/35153673
http://dx.doi.org/10.3389/fnmol.2022.838311
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author Shankhwar, Soni
Schwarz, Karin
Katiyar, Rashmi
Jung, Martin
Maxeiner, Stephan
Südhof, Thomas C.
Schmitz, Frank
author_facet Shankhwar, Soni
Schwarz, Karin
Katiyar, Rashmi
Jung, Martin
Maxeiner, Stephan
Südhof, Thomas C.
Schmitz, Frank
author_sort Shankhwar, Soni
collection PubMed
description Synaptic ribbons are presynaptic specializations that define eponymous ribbon synapses. Synaptic ribbons are largely composed of RIBEYE, a protein containing an N-terminal A-domain and a carboxyterminal B-domain that is identical with CtBP2, a NAD(H)-binding transcriptional co-repressor. Previously we showed that synaptic ribbons are completely absent in RIBEYE knockout mice in which the RIBEYE A-domain-encoding exon had been deleted, but CtBP2 is still made, demonstrating that the A-domain is required for synaptic ribbon assembly. In the present study, we asked whether the RIBEYE B-domain also has an essential role in the assembly of synaptic ribbons. For this purpose, we made use of RIBEYE knockin mice in which the RIBEYE B-domain was replaced by a fluorescent protein domain, whereas the RIBEYE A-domain was retained unchanged. We found that replacing the RIBEYE B-domain with a fluorescent protein module destabilizes the resulting hybrid protein and causes a complete loss of synaptic ribbons. Our results thus demonstrate an essential role of the RIBEYE B-domain in enabling RIBEYE assembly into synaptic ribbons, reinforcing the notion that RIBEYE is the central organizer of synaptic ribbons.
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spelling pubmed-88316972022-02-12 RIBEYE B-Domain Is Essential for RIBEYE A-Domain Stability and Assembly of Synaptic Ribbons Shankhwar, Soni Schwarz, Karin Katiyar, Rashmi Jung, Martin Maxeiner, Stephan Südhof, Thomas C. Schmitz, Frank Front Mol Neurosci Molecular Neuroscience Synaptic ribbons are presynaptic specializations that define eponymous ribbon synapses. Synaptic ribbons are largely composed of RIBEYE, a protein containing an N-terminal A-domain and a carboxyterminal B-domain that is identical with CtBP2, a NAD(H)-binding transcriptional co-repressor. Previously we showed that synaptic ribbons are completely absent in RIBEYE knockout mice in which the RIBEYE A-domain-encoding exon had been deleted, but CtBP2 is still made, demonstrating that the A-domain is required for synaptic ribbon assembly. In the present study, we asked whether the RIBEYE B-domain also has an essential role in the assembly of synaptic ribbons. For this purpose, we made use of RIBEYE knockin mice in which the RIBEYE B-domain was replaced by a fluorescent protein domain, whereas the RIBEYE A-domain was retained unchanged. We found that replacing the RIBEYE B-domain with a fluorescent protein module destabilizes the resulting hybrid protein and causes a complete loss of synaptic ribbons. Our results thus demonstrate an essential role of the RIBEYE B-domain in enabling RIBEYE assembly into synaptic ribbons, reinforcing the notion that RIBEYE is the central organizer of synaptic ribbons. Frontiers Media S.A. 2022-01-28 /pmc/articles/PMC8831697/ /pubmed/35153673 http://dx.doi.org/10.3389/fnmol.2022.838311 Text en Copyright © 2022 Shankhwar, Schwarz, Katiyar, Jung, Maxeiner, Südhof and Schmitz. https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Molecular Neuroscience
Shankhwar, Soni
Schwarz, Karin
Katiyar, Rashmi
Jung, Martin
Maxeiner, Stephan
Südhof, Thomas C.
Schmitz, Frank
RIBEYE B-Domain Is Essential for RIBEYE A-Domain Stability and Assembly of Synaptic Ribbons
title RIBEYE B-Domain Is Essential for RIBEYE A-Domain Stability and Assembly of Synaptic Ribbons
title_full RIBEYE B-Domain Is Essential for RIBEYE A-Domain Stability and Assembly of Synaptic Ribbons
title_fullStr RIBEYE B-Domain Is Essential for RIBEYE A-Domain Stability and Assembly of Synaptic Ribbons
title_full_unstemmed RIBEYE B-Domain Is Essential for RIBEYE A-Domain Stability and Assembly of Synaptic Ribbons
title_short RIBEYE B-Domain Is Essential for RIBEYE A-Domain Stability and Assembly of Synaptic Ribbons
title_sort ribeye b-domain is essential for ribeye a-domain stability and assembly of synaptic ribbons
topic Molecular Neuroscience
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8831697/
https://www.ncbi.nlm.nih.gov/pubmed/35153673
http://dx.doi.org/10.3389/fnmol.2022.838311
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