DNA healer

that normally crowd the AIS’s plasma membrane dispersed. When ankyrinG was absent the erstwhile axons began to resemble dendrites, sprouting spines and developing excitatory synapses. Characteristic molecules from the cell body and dendrites, such as the microtubule polymerizing protein MAP2, also infi ltrated the axons. The AIS appears to serve as a fi lter that screens out dendritic proteins, Hedstrom et al. conclude. How the structure bars some proteins from the axon is still uncertain. Injuries and diseases can transform dendrites into axons. The fi ndings raise the possibility that these insults could cause the reverse transformation by changing the amount of ankyrinG and altering the AIS. Hedstrom, K.L., et al. 2008. J. Cell Biol. doi:10.1083/jcb.200806112.