We have developed a new technology called SYNMAP that reveals the proteins in billions of individual synapses – the junctions between nerve cells – in all areas of the brain across the whole lifespan of the mouse (Cizeron et al. (2020). Science 369, 270-275). This roadmap of the brain, called the Lifespan Synaptome Architecture (LSA), provides an important new resource for understanding how the brain develops and changes with natural ageing, with important implications for the human brain. The three phases seen in the mouse LSA (I, II, III), which describe a rapid expansion, peak and then gradual decline in synapse diversity, correspond in time to human childhood, adulthood and old age, respectively, and correlate with the known trajectory of human intellectual ability. Crucially, in the future researchers will be able to use the LSA to identify exactly when and where psychiatric and neurological disorders such as schizophrenia and autism, which have characteristic ages of onset, damage the brain. Furthermore, the LSA may help in efforts to counter natural or genetic brain dysfunction – for example, in revealing the benefits for the brain of environmental enrichment or cognitive therapy.
A systematic mapping of the molecular and morphological features of individual excitatory synapses across the brain and throughout the lifespan in the mouse. The atlas data resource provides synaptome mapping data across all brain regions and lifespan of the mouse in a user-friendly, interactive setting.