A stream of cells migrating from the caudal telencephalon reveals a link between the amygdala and neocortex.
The amygdaloid complex consists of diverse nuclei that belong to distinct functional systems, yet many issues about its development are poorly understood. Here, we identify a stream of migrating cells that form specific amygdaloid nuclei in mice. In utero electroporation showed that this caudal amygdaloid stream (CAS) originated in a unique domain at the caudal telencephalic pole that is contiguous with the dorsal pallium, which was previously thought to generate only neocortical cells. The CAS and the neocortex share mechanisms for specification (transcription factors Tbr1, Lhx2 and Emx1/2) and migration (reelin and Cdk5). Reelin, a critical cue for migration in the neocortex, and Cdk5, which is specifically required for migration along radial glia in the neocortex, were both selectively required for the normal migration of the CAS, but not for that of other amygdaloid nuclei. This is first evidence of a dorsal pallial contribution to the amygdala, demonstrating a developmental and mechanistic link between the amygdala and the neocortex.
Remedios
Ryan
R
Department of Biological Sciences, B-304, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India.
Huilgol
Dhananjay
D
Saha
Bhaskar
B
Hari
Padmanabhan
P
Bhatnagar
Lahar
L
Kowalczyk
Thomas
T
Hevner
Robert F
RF
Suda
Yoko
Y
Aizawa
Shinichi
S
Ohshima
Toshio
T
Stoykova
Anastassia
A
Tole
Shubha
S
D000679:Amygdala / Q000166:cytology* / Q000502:physiology*; D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000378:metabolism; D002465:Cell Movement / Q000235:genetics / Q000502:physiology*; D051360:Cyclin-Dependent Kinase 5 / Q000378:metabolism; D018274:Electroporation / Q000379:methods; D004622:Embryo, Mammalian; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007150:Immunohistochemistry / Q000379:methods; D017403:In Situ Hybridization / Q000379:methods; D051379:Mice; D008817:Mice, Mutant Strains; D019579:Neocortex / Q000166:cytology* / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D000091042:Reelin Protein; D012697:Serine Endopeptidases / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
D015816:Cell Adhesion Molecules, Neuronal; D016326:Extracellular Matrix Proteins; D009419:Nerve Tissue Proteins; D000091042:Reelin Protein; D014157:Transcription Factors; D049452:Green Fluorescent Proteins; D051360:Cyclin-Dependent Kinase 5; C000717128:Reln protein, mouse; D012697:Serine Endopeptidases