Early events in axon/dendrite polarization.
Differentiation of axons and dendrites is a critical step in neuronal development. Here we review the evidence that axon/dendrite formation during neuronal polarization depends on the intrinsic cytoplasmic asymmetry inherited by the postmitotic neuron, the exposure of the neuron to extracellular chemical factors, and the action of anisotropic mechanical forces imposed by the environment. To better delineate the functions of early signals among a myriad of cellular components that were shown to influence axon/dendrite formation, we discuss their functions by distinguishing their roles as determinants, mediators, or modulators and consider selective degradation of these components as a potential mechanism for axon/dendrite polarization. Finally, we examine whether these early events of axon/dendrite formation involve local autocatalytic activation and long-range inhibition, as postulated by Alan Turing for the morphogenesis of patterned biological structure.
Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan. plcheng@imb.sinica.edu.tw
Pei-lin
PL
Cheng
Mu-ming
MM
Poo
D000818:Animals; D001369:Axons / Q000502:physiology*; D016764:Cell Polarity / Q000502:physiology*; D003712:Dendrites / Q000502:physiology*; D008959:Models, Neurological; D009414:Nerve Growth Factors / Q000502:physiology; D055495:Neurogenesis / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology
D009414:Nerve Growth Factors