Scientists from the National University of Singapore (NUS) are the first in the world to identify juxtanodin, a novel protein of the nervous system, and to reveal its biological functions in controlling the development of oligodendroglia, the specialized brain cells responsible for insulating the brain signaling network. The findings may open up opportunities for better understanding and more effective treatment of diseases such as multiple sclerosis and schizophrenia.
Hundreds of different disorders affect the central nervous system, comprising the brain and the spinal cord, thus complicating efforts to prevent and treat them. Neurological disorders constitute one of the major disease groups afflicting many Singaporeans. According to the report on the Global Burden of Neurological Disease by the World Federation of Neurology task force, 1 in 9 deaths worldwide is due to neurological disorders .
Identification of novel gene contributes to better understanding of neurological disorders
A team of NUS research scientists from the Department of Anatomy, Yong Loo Lin School of Medicine at NUS, have identified an oligodendroglia-specific novel gene/protein called juxtanodin, a name coined by the researchers who discovered it. The researchers have also explained its roles in controlling the development of oligodendroglia. The team, led by Dr Liang Fengyi, made the discovery while screening cell type-specific genes in the nervous system.
Professor John Wong, Vice President (Research/Life Sciences) and Dean, Yong Loo Lin School of Medicine, NUS said, "The identification and functional characterization of a novel protein in the brain, namely juxtanodin, is a significant contribution to understanding how the brain works. The authors' findings is yet another step forward in our quest to develop better therapies for our patients. We are proud that work of this quality is becoming a regular feature at the National University of Singapore. Publishing original work from Singapore in the Proceedings of the National Academy of Sciences, USA is a major achievement. "
About Oligodendroglia
Neural signaling controls what we think, do and sense. Nerve fibers, which form the neural signaling network, are insulated by a white fatty material called myelin sheath. Insulation of the neural signaling network is essential to accelerate propagation of the signals, to prevent miscommunication, to support the signaling cells (neurons) and to maintain the integrity of the nervous system. Oligodendroglia are the non-neuronal brain cells responsible for the formation of myelin around the nerve fibers.
Abnormalities in the development of oligodendroglia may result in improper laying down (dysmyelination) or destruction (demyelination) of the insulation wrap (myelin sheath) around the signaling nerve fibers, causing diverse neurological or psychiatric diseases ranging from multiple sclerosis (MS), postinfectious encephalomyelitis to leukodystrophy and schizophrenia (please refer to Annex 1 on a brief description of these diseases). Oligodendroglia-associated molecules are also linked to regeneration after brain or spinal cord injury.
Role and Functions of Juxtanodin
Myelin sheath or the insulation wrap is formed and maintained by cellular events such as the development of cellular branches and the delivery of proteins along the cellular branches. As such, the scientific community suspected that malfunction of these cellular events may be the cause of many of the aforementioned neurological diseases.
In their recent study, the NUS team found that the novel juxtanodin protein speeded up the development of oligodendroglia in culture: cells endowed with the juxtanodin protein developed longer cellular branches, intensified the expression of another functional protein in the same cells, and increased delivery of the latter protein to the cellular branches.
Through the identification and functional characterization of novel oligodendroglial genes/proteins, the research team hopes to explain the mechanisms controlling oligodendroglia development or myelin formation/maintenance, and to reveal new clues about the causes and treatments of demyelinating or degenerative neurological diseases such as multiple sclerosis and postinfectious encephalomyelitis.
Therefore, further investigation along this track would contribute to the search for pharmacological or molecular means to specifically regulate and reinstate deranged oligodendroglia functions that may ultimately improve or alleviate the neurological disorders of the affected individual. If this is achieved, it could be possible to control and correct disorders of oligodendroglia development through genetic engineering.
The findings of the NUS study have just been published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS), a multidisciplinary journal that disseminates the work done by leading researchers and reaches more than 25,000 institutions and individuals worldwide. PNAS is one of the most cited scientific journals in the world .
