Ferret-mouse differences in interkinetic nuclear migration and cellular densification in the neocortical ventricular zone.
The thick outer subventricular zone (OSVZ) is characteristic of the development of human neocortex. How this region originates from the ventricular zone (VZ) is largely unknown. Recently, we showed that over-proliferation-induced acute nuclear densification and thickening of the VZ in neocortical walls of mice, which lack an OSVZ, causes reactive delamination of undifferentiated progenitors and invasion by these cells of basal areas outside the VZ. In this study, we sought to determine how VZ cells behave in non-rodent animals that have an OSVZ. A comparison of mid-embryonic mice and ferrets revealed: (1) the VZ is thicker and more pseudostratified in ferrets. (2) The soma and nuclei of VZ cells were horizontally and apicobasally denser in ferrets. (3) Individual endfeet were also denser on the apical (ventricular) surface in ferrets. (4) In ferrets, apicalward nucleokinesis was less directional, whereas basalward nucleokinesis was more directional; consequently, the nuclear density in the periventricular space (within 16 μm of the apical surface) was smaller in ferrets than in mice, despite the nuclear densification seen basally in ferrets. These results suggest that species-specific differences in nucleokinesis strategies may have evolved in close association with the magnitudes and patterns of nuclear stratification in the VZ.
Mayumi
M
Okamoto
Tomoyasu
T
Shinoda
Takumi
T
Kawaue
Arata
A
Nagasaka
Takaki
T
Miyata
D021581:Active Transport, Cell Nucleus / Q000502:physiology*; D000818:Animals; D030801:Animals, Genetically Modified; D002453:Cell Cycle; D002467:Cell Nucleus / Q000502:physiology*; D004622:Embryo, Mammalian; D005136:Eye Proteins / Q000378:metabolism; D005260:Female; D005289:Ferrets; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism; D020547:Lateral Ventricles / Q000166:cytology*; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D019579:Neocortex / Q000033:anatomy & histology* / Q000196:embryology; D058953:Neural Stem Cells / Q000502:physiology*; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors / Q000378:metabolism; D011247:Pregnancy; D012097:Repressor Proteins / Q000378:metabolism; D013045:Species Specificity; D018709:Statistics, Nonparametric; D062826:Zonula Occludens-1 Protein / Q000378:metabolism
D005136:Eye Proteins; D018398:Homeodomain Proteins; D008562:Membrane Glycoproteins; D000071841:PAX6 Transcription Factor; C000605730:PAX6 protein, human; D051761:Paired Box Transcription Factors; C000605732:Pax6 protein, mouse; D012097:Repressor Proteins; D062826:Zonula Occludens-1 Protein; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins