CENTER FOR GENETIC ANALYSIS OF BEHAVIOR

Outline

This center produces gene modified rat/mouse and analyzes their behavior using multiple parameters under normal and various stressful conditions. The facilities in this center are open for the collaboratory use from researchers all over Japan.

Director

Professor: SHIGEMOTO, Ryuichi, PhD

Our research subjects include two major projects as follows.

First, we have focused on the reproductive biotechnology to understand gamete interactions during fertilization and the development of novel methodology to produce transgenic animals. Among them, we have a special interest in the increasing demand for production of gene-targeted (KO: knock-out) rats because use of rats rather than mice is advantageous in aspects of microsurgery and mapping of brain functions. Embryonic stem cell line and nuclear transfer (cloning) protocol have not yet been established in rats, attributing to slow progress of brain research. At present, we devote all our skills (e.g. in vitro fertilization, animal cloning, microinsemination, spermatogonial transplantation) to look for the possibility of producing KO rats, and also provide collaborative services to produce conventional knock out mice, and transgenic mice and rats by pronuclear DNA microinjection or intracytoplasmic sperm injection (ICSI)-mediated DNA transfer.

Second, by using techniques of rodent transgenesis, we have analyzed the molecular and cellular mechanisms to form functional ocular dominance (OD) columns in the primary visual cortex. OD columns are known to be fundamental units of processing visual information to sense depth, and are anatomically well documented as models in the research area of neuronal plasticity. Coarse OD columns are set up around birth, which are subsequently remodeled to the functional structure by visual activity after eye open. Our final goal is to understand the comprehensive story underlying formation of functional OD columns, which can be achieved by taking advantage of molecular markers specific for developing OD columns that we have originally isolated.

Advanced Reproductive Technology in Rats

Fig.1 Spermatogonial transplantation in rats
Fate of transplanted spermatogonial cells; Donor spermatogonial stem cells originated from EGFP-Tg rats can proliferate and differentiate in the recipient seminiferous tubules of c-myc -Tg rats (three months after the spermatogonial transplantation).

Fig.2 Intracytoplasmic sperm injection in rats
Production of fertilized rat oocytes by intracytoplasmic sperm injection (ICSI); A single fishhook-shaped sperm head is microinjected into ovulated and denuded oocytes with the aid of Piezo-micromanipulators.

Ocular Dominance (OD) Column

Fig.3 Process of OD column formation
Coarse OD columns are set up around birth, and are subsequently instructed by incoming visual inputs to become functional structure after eye open.

Staff

Section of Metabolic Physiology

This section analyzes the in vivo neuronal and metabolic activity in mice and rats which were modified their genes and exposed with various environmental conditions. This section examines the following subjects and will be open for the collaboratory use of researchers all over Japan from April, 2011:

1) Single unit recording from motor related brain regions in awake state.

2) Neurotransmitter release in local brain regions in free-moving animals.

3) Regional neural activity detected as intrinsic signals with taking the advantage of light fluorescent dynamics of flavin or hemoglobin.

4) Energy intake and expenditure in free-moving animals.

5) Body temperature, heart rate and blood pressure in free-moving animals.

6) EEG (Electroencephalogram) in free-moving animals.

Staff

Section of Behavior Patterns

The section of behavior patterns was established on 1 April, 2007. Dr. T. Miyakawa assumed the position of the Adjunct Professor of the section. The purpose of our research group is to evaluate the functional significances of genes expressed in the brain and the endophenotype of psychiatric disorders by performing a behavioral test battery and functional brain analyses on genetically engineered mice.

Since April 2009, we are capable of conducting a comprehensive behavioral test buttery for mice. We will widely accept collaborative projects such as general collaborative projects and planned collaborative projects.

Staff