Cortical neuronal migration mutants suggest separate but intersecting pathways.
During brain development, neurons migrate great distances from proliferative zones to generate the cortical gray matter. A series of studies has identified genes that are critical for migration and targeting of neurons to specific brain regions. These genes encode three basic groups of proteins and produce three distinct phenotypes. The first group encodes cytoskeletal molecules and produces graded and dosage-dependent effects, with a significant amount of functional redundancy. This group also appears to play important roles during the initiation and ongoing progression of neuronal movement. The second group encodes signaling molecules for which homozygous mutations lead to an inverted cortex. In addition, this group is responsible for movement of neurons through anatomic boundaries to specific cortical layers. The third group encodes enzymatic regulators of glycosylation and appears to delineate where neuronal migration will arrest. There is significant cross-talk among these different groups of molecules, suggesting possible points of pathway convergence.
Neurogenetics Laboratory, Department of Neurosciences, University of California-San Diego, La Jolla, CA 92093-0624, USA. sbielas@ucsd.edu
Stephanie
S
Bielas
Holden
H
Higginbotham
Hiroyuki
H
Koizumi
Teruyuki
T
Tanaka
Joseph G
JG
Gleeson
D000818:Animals; D002465:Cell Movement / Q000235:genetics; D002540:Cerebral Cortex / Q000166:cytology / Q000196:embryology*; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism; D006031:Glycosylation; D009154:Mutation / Q000235:genetics; D009474:Neurons / Q000502:physiology*; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology
D003598:Cytoskeletal Proteins; D014157:Transcription Factors