Richter Franziska, Gerstenberger Julia, Bauer Anne, Liang Chun-Chi, Richter Angelika
Institute of Pharmacology, Pharmacy and Toxicology, Department of Veterinary Medicine, Leipzig University, An den Tierkliniken 15, 04103, Leipzig, Germany.
Department of Neurology and Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA.
Behav Brain Res. 2017 Jan 15;317:536-541. doi: 10.1016/j.bbr.2016.10.028. Epub 2016 Oct 18.
Hereditary generalized dystonia is often caused by a GAG deletion in TOR1A (DYT1) that encodes for the protein torsinA. Although mutation carriers show alterations in neuronal connectivity and sensorimotor deficits, only 30% develop dystonia. Uncovering the factors triggering the dystonic symptoms and underlying pathophysiology would greatly benefit the development of more effective therapies. In DYT1 knock-in (KI) mice, the expression of torsinA mutant alters the connectivity of neurons and the function of striatal cholinergic interneurons. We aimed to determine if heterozygous DYT1 KI mice exhibit deficits in behavioural tests that explore the connectivity of the sensory and motor system. DYT1 KI mice were tested in cognitive tests and challenging motor paradigms, followed by the adhesive removal test and the adaptive rotating beam test which both require sensorimotor integration. DYT1 KI mice did not exhibit cognitive deficits and were able to perform similarly to wild type mice even in challenging motor tests with relatively stable sensory input. Conversely, DYT1 KI mice spent more time on sensing and removing an adhesive sticker from the back of the nose; they exhibited difficulty to traverse rotating rods, especially if the surface was smooth and the diameter small. Our observations further support a role of sensorimotor integration in manifestation of this movement disorder. Future studies in DYT1 KI mice will explore the involved neurocircuitry and underlying molecular mechanisms.
遗传性全身性肌张力障碍通常由TOR1A（DYT1）基因中的GAG缺失引起，该基因编码扭转蛋白A。尽管突变携带者表现出神经元连接改变和感觉运动缺陷，但只有30%的人会发展为肌张力障碍。揭示引发肌张力障碍症状的因素和潜在的病理生理学将极大地有助于开发更有效的治疗方法。在DYT1基因敲入（KI）小鼠中，扭转蛋白A突变体的表达改变了神经元的连接性和纹状体胆碱能中间神经元的功能。我们旨在确定杂合DYT1 KI小鼠在探索感觉和运动系统连接性的行为测试中是否存在缺陷。对DYT1 KI小鼠进行认知测试和具有挑战性的运动范式测试，随后进行均需要感觉运动整合的粘胶去除测试和适应性旋转杆测试。DYT1 KI小鼠没有表现出认知缺陷，即使在具有相对稳定感觉输入的具有挑战性的运动测试中，其表现也与野生型小鼠相似。相反，DYT1 KI小鼠在从鼻后部感知和去除粘胶贴纸时花费了更多时间；它们在穿过旋转杆时表现出困难，尤其是当表面光滑且直径较小时。我们的观察结果进一步支持了感觉运动整合在这种运动障碍表现中的作用。未来对DYT1 KI小鼠的研究将探索所涉及的神经回路和潜在的分子机制。
