The role of astrocytic mitochondria in 22q11 deletion syndrome

The 22q11 deletion syndrome (DS) is caused by the loss of a small segment of chromosome 22, which contains many of the genes encoding proteins located in mitochondria, the intra-cellular organelles that play a key role in regulating energy metabolism in the brain. The symptoms of the syndrome vary, but often include developmental delay and changes in the complex cognitive functions that require the normal functioning of the frontal part of the brain cortex. This important area of the brain matures during infancy, which is also when neuronal cells and astrocytes go through a process of maturation. Astrocytes are usually largely overlooked, but it has recently been found that they have the surprising capacity of regulating the maturation of neuronal circuits, particularly those of the frontal cortex. It also interesting to note that the astrocytes in this area of the brain are also involved in mitochondrial functioning not only because they contain a large number of mitochondria, but also because they rely on mitochondria for their own maturation. Our laboratory studies have recently revealed altered mitochondria and delayed astrocyte development in the frontal cortex of a mouse model of 22q11DS. The aim of this project is to assess the role of mitochondria and delayed astrocyte development in the onset of cognitive impairments of 22q11DS in order to identify possible new therapeutic targets.