Basic technology for dynamics and control of neural circuit

Yuchio Yanagawa (Gunma University)

“Establishment of an inhibitory neuron-specific gene expression system using genetically engineered mice together with viral vectors”

Inhibitory neurons are composed of GABAergic and glycinergic neurons. Glutamate decarboxylase 67 (GAD67) and Glycine transporter 2 (GlyT2) are specifically expressed in GABAergic and glycinergic neurons, respectively. Vesicular GABA transporter (VGAT) is present in both GABAergic and glycinergic neurons. Inhibitory neurons are primarily scattered around throughout the CNS, and thus can be hardly identified in live brain preparations. On the other hand, fluorescent proteins such as GFP and tdTomato and functional probes such as channelrhodopsin and calcium indicator have been developed and applied to research on neuronal circuits. However, it is difficult to specifically and stably express a fluorescent protein or a functional probe in a particular neuron type and to switch their expression on or off. Therefore, we are addressing the followings:
1: Based on a tetracycline-controlled transcriptional regulation (Tet) system, we will develop a method that combines tetracycline-controlled transactivator (tTA) knock-in mice and viral-mediated transfer to genetically label and manipulate an inhibitory neuron type in the mouse brain.
2: A variety of viral vectors carrying a fluorescent protein or a functional probe will be applied to study of inhibitory neurons. The Tet system will enable us to switch genes of interest on or off.


 
Recent Publications
1. Fuzik J, Zeisel A, Máté Z, Calvigioni D, Yanagawa Y, Szabó G, Linnarsson S, Harkany T. (2016) Integration of electrophysiological recordings with single-cell RNA-seq data identifies neuronal subtypes. Nature Biotechnol. 34, 175-183.
2. Fujihara K, Miwa H, Kakizaki T, Kaneko R, Mikuni M, Tanahira C, Tamamaki N, Yanagawa Y. (2015) Glutamate Decarboxylase 67 Deficiency in a Subset of GABAergic Neurons Induces Schizophrenia-Related Phenotypes. Neuropsychopharmacology. 40: 2475-86.
3. Tomioka R, Sakimura K, Yanagawa Y. (2015) Corticofugal GABAergic projection neurons in the mouse frontal cortex. Front Neuroanat. 9: 133.
4. Saito Y, Zhang Y, Yanagawa Y. (2015) Electrophysiological and morphological properties of neurons in the prepositus hypoglossi nucleus that express both ChAT and VGAT in a double-transgenic rat model. Eur J Neurosci. 41: 1036-48.

Posted:2016/03/10