Neuronal Polarity: Demarcation, growth, commitment

ALFREDO CACERES, BING YE AND CARLOS DOTTI

CURRENT OPINION IN CELL BIOLOGY

CURRENT BIOLOGY LTD

Lugar: Londres; Año: 2012 vol. 24 p. 1 - 7

0955-0674

Summary In a biological sense, polarity refers to extremity of the main axis of a nucleus, cell, or organism. Classical examples of polarization are the fertilized oocyte and migratory, epithelial and neuronal cells. In neurons, morphological polarity begins with the appearance of the first neurite from the cell body of a newborn neuron. In multipolar neurons, a second phase of polarization occurs when a single neurite, among many sibling ones, initiates a phase of rapid growth becoming the neuron’s axon, while the others remain transiently unchanged, to later differentiate as dendrites. Finally, during a third phase of polarization, nascent axons and dendrites develop an elaborate architecture, acquiring special morphological and molecular features, that commit them to their final axonal or dendritic identities. Mechanistically, each phase of polarization must be preceded by spatial restriction of growth activity. Here, we will review recent work, which is helping to define mechanisms underlying the polarized growth of neurons