Aperçu: G.M.
La
protéine SH3 d'échafaudage postsynaptique SH3 et les domaines multiples
de répression ankyrine 3 (SHANK3) sont essentiels au développement et à
la fonction des synapses glutamatériques. La
perturbation du gène codant pour SHANK3 a été fortement impliquée comme
une cause monogénique de l'autisme, et les souris mutantes Shank3
montrent des gestes répétitifs et des déficits d'interaction sociale.
Les résultats de l'étude démontrent directement l'existence de changements distincts
entre 2 voies striatales dans un modèle d'autisme de la souris et
indiquent que la perturbation indirecte de la bande striatale pourrait
jouer un rôle de causalité dans le comportement répétitif des souris
Shank3B mutantes.
J Clin Invest. 2017 Apr 17. pii: 87997. doi: 10.1172/JCI87997.
Striatopallidal dysfunction underlies repetitive behavior in Shank3-deficient model of autism
Wang W, Li C, Chen Q, van der Goes MS, Hawrot J, Yao AY, Gao X, Lu C, Zang Y, Zhang Q, Lyman K, Wang D, Guo B, Wu S, Gerfen CR, Fu Z, Feng G.
Abstract
The
postsynaptic scaffolding protein SH3 and multiple ankyrin repeat
domains 3 (SHANK3) is critical for the development and function of
glutamatergic synapses. Disruption of the SHANK3-encoding gene has been
strongly implicated as a monogenic cause of autism,
and Shank3 mutant mice show repetitive grooming and social interaction
deficits. Although basal ganglia dysfunction has been proposed to
underlie repetitive behaviors, few studies have provided direct evidence
to support this notion and the exact cellular mechanisms remain largely
unknown. Here, we utilized the Shank3B mutant mouse model of autism
to investigate how Shank3 mutation may differentially affect
striatonigral (direct pathway) and striatopallidal (indirect pathway)
medium spiny neurons (MSNs) and its relevance to repetitive grooming
behavior in Shank3B mutant mice. We found that Shank3 deletion
preferentially affects synapses onto striatopallidal MSNs.
Striatopallidal MSNs showed profound defects, including alterations in
synaptic transmission, synaptic plasticity, and spine density.
Importantly, the repetitive grooming behavior was rescued by selectively
enhancing the striatopallidal MSN activity via a Gq-coupled human M3
muscarinic receptor (hM3Dq), a type of designer receptors exclusively
activated by designer drugs (DREADD). Our findings directly demonstrate
the existence of distinct changes between 2 striatal pathways in a mouse
model of autism
and indicate that the indirect striatal pathway disruption might play a
causative role in repetitive behavior of Shank3B mutant mice.
- PMID: 28414301
- DOI: 10.1172/JCI87997
Aucun commentaire:
Enregistrer un commentaire