Neural vulnerability in Huntington’s disease tied to release of mitochondrial RNA
In the first study to comprehensively track how different types of brain cells respond to the mutation that causes Huntington’s disease (HD), MIT neuroscientists found that a significant cause of death for an especially afflicted kind of neuron might be an immune response to genetic material errantly released by mitochondria, the cellular components that provide cells with energy. In different cell types at different stages of disease progression, the researchers measured how levels of RNA differed from normal in brain samples from people who died with Huntington’s disease and in mice engineered with various degrees of the genetic mutation. Among several novel observations in both species, one that particularly stood out is that RNA from mitochondria were misplaced within the brain cells, called spiny projection neurons (SPNs), that are ravaged in the disease, contributing to its fatal neurological symptoms. The scientists observed that these stray RNAs, which look different to cells...