A new function has been found for the amyloid precursor protein (APP), which may help explain how it goes awry in Alzheimer's disease. It appears that APP (which is involved in the creation of amyloid-beta), also helps control the growth and maturation of newborn brain cells, by regulating a specific microRNA (microRNA-574-5p) that normally promotes neurogenesis.
 Amyloid precursor protein regulates neurogenesis by antagonizing miR-574-5p in the developing cerebral cortex. Nature Communications. 5,(2014).