Autism associated SHANK3 missense point mutations impact conformational fluctuations and protein turnover at synapses
- Humboldt-Universität zu Berlin, Institute of Biology, Germany
- European Molecular Biology Laboratory, Germany
- University Medical Centre Hamburg-Eppendorf, Germany
- Korea Advanced Institute of Science and Technology, Republic of Korea
- Washington State University, United States
- Leibniz-Institute for Neurobiology, Germany
Abstract
Members of the SH3- and ankyrin-rich repeat (SHANK) protein family are considered as master scaffolds of the post-synaptic density of glutamatergic synapses. Several missense mutations within the canonical SHANK3 isoform have been proposed as causative for the development of autism spectrum disorders (ASDs). However, there is a surprising paucity of data linking missense mutation-induced changes in protein structure and dynamics to the occurrence of ASD-related synaptic phenotypes. In this proof-of-principle study, we focus on two ASD-associated point mutations, both located within the same domain of SHANK3 and demonstrate that both mutant proteins indeed show distinct changes in secondary and tertiary structure as well as higher conformational fluctuations. Local and distal structural disturbances result in altered synaptic targeting and changes of protein turnover at synaptic sites in rat primary hippocampal neurons.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Dmitry Molodenskiy
Hans-Jürgen Kreienkamp
Funding
Deutsche Forschungsgemeinschaft (MI1923/1-2)
- Marina Mikhaylova
Deutsche Forschungsgemeinschaft (FOR2419 TP2)
- Marina Mikhaylova
Deutsche Forschungsgemeinschaft (EXC-2049-390688087)
- Marina Mikhaylova
Leibniz-Gemeinschaft (Neurotranslation)
- Michael R Kreutz
Deutscher Akademischer Austauschdienst (Research Stays for University Academics and Scientists Award)
- Alla S Kostyukova
Hamburg Landesforschungsförderung (LFF-FV76)
- Marina Mikhaylova
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal experiments were carried out in accordance with the European Communities Council Directive (2010/63/EU) and the Animal Welfare Law of the Federal Republic of Germany (Tierschutzgesetz der Bundesrepublik Deutschland, TierSchG) approved by the local authorities of the city-state Hamburg (Behörde für Gesundheit und Verbraucherschutz, Fachbereich Veterinärwesen) and the animal care committee of the University Medical Center Hamburg-Eppendorf.
Copyright
© 2021, Bucher et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Autism associated SHANK3 missense point mutations impact conformational fluctuations and protein turnover at synapses
eLife 10:e66165.
https://doi.org/10.7554/eLife.66165
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