Area Patterning of the Mammalian Cortex

Neuron. 2007 Oct 25;56(2):252-69. doi: 10.1016/j.neuron.2007.10.010.

Abstract

Here we describe mechanisms regulating area patterning of developing mammalian neocortex, referred to as arealization. Current findings indicate an interplay between intrinsic genetic mechanisms and extrinsic information relayed to cortex by thalamocortical input. Intrinsic mechanisms are based on morphogens and signaling molecules secreted by patterning centers, positioned at the perimeter of dorsal telencephalon, that generate across nascent cortex the graded expression of transcription factors in cortical progenitors. Two major patterning centers are the commissural plate, which expresses Fgf8 and Fgf17, and the cortical hem, which expresses Bmps and Wnts. Four transcription factors, COUP-TFI, Emx2, Pax6, and Sp8, with graded expression across the embryonic cortical axes, are shown to determine sizes and positions of cortical areas by specifying or repressing area identities within cortical progenitors. They also interact to modify their expression, as well as expression of Fgf8. We review these mechanisms of arealization and discuss models and concepts of cortical area patterning.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Body Patterning*
  • Cerebral Cortex / embryology*
  • Cerebral Cortex / metabolism
  • Cerebral Cortex / physiology
  • Fibroblast Growth Factor 8 / genetics
  • Fibroblast Growth Factor 8 / metabolism
  • Gene Expression Regulation, Developmental
  • Genotype
  • Humans
  • Mammals / embryology*
  • Mammals / genetics
  • Mammals / physiology
  • Models, Biological

Substances

  • Fibroblast Growth Factor 8