Shank3a Regulates the Susceptibility to Seizure and Thalamocortical Connectivity
Abstract number :
3.058
Submission category :
1. Basic Mechanisms / 1E. Models
Year :
2021
Submission ID :
1825562
Source :
www.aesnet.org
Presentation date :
12/6/2021 12:00:00 PM
Published date :
Nov 22, 2021, 06:44 AM
Authors :
Sayaka Okuzono, MD - Kyushu University; Yasunari Sakai, MD, PhD - Kyushu Univeristy; Yuki Matsushita, MD, PhD - Kyushu University; Daiki Setoyama, MD, PhD - Kyushu University; Yohei Shinmyo, MD, PhD - Kanazawa University; Ryoji Taira, MD - Kyushu University; Kouji Yonemoto, MD - Kyushu University; Satoshi Akamine, MD, PhD - Kyushu University; Yoshitomo Motomura, MD, PhD - Kyushu University; Masafumi Sanefuji, MD, PhD - Kyushu University; Takeshi Sakurai, MD, PhD - Kyoto University; Hiroshi Kawasaki, MD, PhD - Kanazawa University; Kihoon Han, MD, PhD - Korea University College of Medicine; Dongchon Kang, MD, PhD - Kyushu University; Yusaku Nakabeppu, MD, PhD - Kyushu University; Shouichi Ohga, MD, PhD - Kyushu University
Rationale: SH3 and multiple ankyrin repeat domains 3 encodes an autism spectrum disorder (ASD)-associated protein Shank3. Of the known isoforms, Shank3a contains ankyrin repeat domain (Ank) near the amino terminus. Little is known, however, about whether Shank3a plays a unique role in the postnatal development.
Methods: All experimental methods were approved by the Institutional Review Board at Kyushu University and the Institutional Animal Care and Use Committee. Shank3a-knockout (KO) mice were maintained in a specific-pathogen-free environment. Four-week-old male littermates were used for kainic acid treatments. Primary somatosensory cortices were coronally or tangentially sectioned for cytochrome oxidase histochemistry and immunofluorescence with anti-Vglut2 and 5HT antibodies. Neuro2a cells were transfected with either GFP or GFP-Shank3a-ankyrin-repeat-domain expression vectors. Whole cell lysates were subjected to co-immunoprecipitation with anti-GFP antibody (D153-11). CBB-positive regions of the electrophoresis gel were cut into small pieces, and then subjected to in-gel digestion for mass spectrometry.
Results: We found that Shank3a was expressed in the thalamic nuclei, hippocampus and cerebral cortex at postnatal two to four weeks. Shank3a-knockout mice showed lower parvalbumin signals in the thalamic nuclei, but formed more hyperintense signals of the barrel structure at the primary somatosensory cortex than did wild-type mice at four weeks. Kainic acid treatments revealed that Shank3a-knockout mice were more susceptible to the exacerbation of generalized seizures than wild-type mice. In vitro studies confirmed that Shank3a-Ank anchored Dkk1 inside Neuro2a cells, thereby regulating the physiological activation of Wnt signals.
Conclusions: These data suggested that Shank3a coordinates molecular signals for the acquisition of excitation-inhibition balance in thalamocortical connectivity and the postnatal development of the sensory system.
Funding: Please list any funding that was received in support of this abstract.: This study was supported by JSPS KAKENHI grant numbers JP19K08281; AMED under the grant number JP20ek0109411, JP20wm0325002h; a research grant for prion diseases from the Ministry of Health, Labour and Welfare of Japan (JP20FC1054); The Japan Epilepsy Research Foundation, and Kawano Masanori Memorial Public Interest Incorporated Foundation for Promotion of Pediatrics (Sakai).
Basic Mechanisms