Dap12-deficient mouse brain (1 month)

Polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLOSL) is an inherited brain and bone disease. It manifests as dementia and bone fractures. The PLOSL phenotype is caused by loss-of-function mutations in one of the two genes encoding the components of the DAP12/TREM2 receptor complex. The DAP12/TREM2 complex is expressed in cells of the myeloid lineage, including microglia in the central nervous system (CNS). The molecular mechanisms producing the CNS phenotype of PLOSL remain largely unknown. To gain insight into dysfunctional CNS pathways behind PLOSL, we performed genome-wide expression analysis of Dap12 (Tyrobp)-deficient mouse brain. In Dap12-deficient mice, we observed alterations in several pathways involved in synaptic function. In agreement with the myelin loss in PLOSL patients, we also saw changes in transcript levels of genes encoding myelin components. Keywords: knockout response Transcript profiles of the midbrain (diencephalon and basal ganglia) of three Dap12-knockout and three heterozygous mice were analyzed.