Scientists from the Stanford University School of Medicine have identified a molecule that acts as a switch triggering brain cells to grow and develop. Molecules known as miR-219 are usually found at high levels in brain cells called oligodendrocytes. This molecules seem to trigger oligodendrocytes to undergo a maturation process and become adult cells that perform certain tasks such as producing myelin, the protein that acts as insulation for neurons in the brain.
Oligodendrocytes are highly important cells found in the brain. Four out of ten cells in the brain are oligodendrocytes. Once mature, these cells are the ones that produce the myelin coating in the nerve cells that ensure more efficient transmission of nerve impulses. Lack of myelin coating is connected to diseases such as multiple sclerosis.
Among the oligodendrocytes that exist in the brain, there are also several precursor cells that may be found in the brain that are destined to become oligondendrocytes. But they remain in an immature and suspended state that falls between a stem cell and an adult oligodendrocyte. Researchers have previously no idea on how the precursor cells turn into adult oligodendrocytes. Everything was a mystery until the Stanford researchers discovered about mi-219.
According to Dr. Ben Barres, MD, PhD, professor and chair of neurobiology at Stanford University School of Medicine and lead author of the said study, "The mechanism responsible for this shifting of anatomical and behavioral gears from precursor to fully functioning dendrochronology was a mystery. Finding this switch has allowed us to ferret out several of the molecules it acts on inside cells. And that in turn could open the door to new approaches to treating diseases where dendrochronology precursors’ failure to mature appropriately plays a role."