Data from: Neurotrophins induce fission of mitochondria along embryonic sensory axons

Neurotrophins are growth factors that have a multitude of roles in the
nervous system. We report that neurotrophins induce the fission of
mitochondria along embryonic chick sensory axons driven by combined PI3K
and Mek-Erk signaling. Following an initial burst of fission a new steady
state of neurotrophin-dependent mitochondria length is established.
Mek-Erk controls the activity of the fission mediator Drp1 GTPase, while
PI3K may contribute to the actin dependent aspect of fission.
Drp1-mediated fission is required for nerve growth factor (NGF) induced
collateral branching in vitro and expression of dominant negative Drp1
impairs the branching of axons in the developing spinal cord in vivo.
Fission is also required for NGF-induced mitochondria-dependent
intra-axonal translation of the actin regulatory protein cortactin, a
previously determined component of NGF-induced branching. Collectively,
these observations unveil a novel biological function of neurotrophins;
the regulation of mitochondrial fission and steady state mitochondrial
length and density in axons.