MAPK8 and early-onset autosomal dominant Alzheimer disease: DLK/JNK-mediated retrograde injury signaling is important in both in vitro and in vivo models of axonal insults (Cavalli et al., 2005; Sengupta Ghosh et al., 2011), and retrograde signaling of axonally-translated ATF4 has been implicated in models of Alzheimer’s disease (Baleriola et al., 2014).