A joint research team of the Daegu Gyeongbuk Institute of Science and Technology (DGIST) and Seoul National University discovered a protein that plays a crucial role in regulating brain signal transmission.

The researchers unveiled a new mechanism of the synaptic adhesion protein called "Protein Tyrosine Phosphatase sigma" (PTP-sigma) in some neural circuits of the hippocampus, providing clues for brain disorder treatments.

Most mental illnesses, such as depression, autism, schizophrenia, and Alzheimer's disease, are deeply related to dysfunction of the brain's synaptic adhesion proteins. However, the specific function of the adhesive protein has not been clarified.

A synapse is a basic unit of information transmission that plays a crucial role in connecting nerve cells. It consists of presynapse and postsynapse. If the function of synaptic adhesion protein is abnormal, there is a problem with neural circuit connection and brain disease.

The team confirmed that PTP-sigma is a critical factor that directs neurotransmitter release as a presynaptic adhesive protein through a PTP-sigma conditional knockout mouse, one of the synaptic adhesive proteins.

It also found that PTP-sigma protein did not affect the response of postsynaptic glutamic acid receptors in specific neural circuits in the hippocampus.

"The study proved the function of a specific neural circuit of the hippocampus and the general function of the synaptic adhesion protein PTP-sigma, which is involved in the development of the nervous system," DGIST Professor Ko Jae-won said.