Identification of molecules preferentially expressed beneath the marginal zone in the developing cerebral cortex.
During cerebral cortical development, the majority of excitatory neurons are born near the ventricle and migrate radially toward the marginal zone (MZ). Since the cells invariably stop migrating beneath the MZ, neurons are aligned in an "inside-out" manner in the cortical plate (CP); that is, the early-born and late-born neurons are ultimately positioned in the deep and superficial layers, respectively. Since dramatic morphological changes occur in cells beneath the MZ, several events critical for proper neuronal maturation and layer formation must take place. In this study, we screened for molecules strongly expressed beneath the MZ, and identified 28 genes that are preferentially expressed in the upper half of the mouse CP on both embryonic day (E) 16.5 and E18.5. Expression analyses in reeler and yotari mice, in which neurons terminate migration throughout the CP, suggested that these genes were indeed related to the events beneath the MZ rather than unrelatedly induced by the structures near the brain surface. Pathway analyses suggested calcium signaling to have an important role in cells beneath the MZ. The gene list presented here will be useful for clarifying the molecular mechanisms that control cortical development.
Department of Anatomy, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
Kashiko
K
Tachikawa
Shinji
S
Sasaki
Takuya
T
Maeda
Kazunori
K
Nakajima
D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000172:deficiency; D002540:Cerebral Cortex / Q000033:anatomy & histology / Q000196:embryology / Q000378:metabolism; D018274:Electroporation / Q000379:methods; D004622:Embryo, Mammalian; D016326:Extracellular Matrix Proteins / Q000172:deficiency; D005260:Female; D015870:Gene Expression / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D049452:Green Fluorescent Proteins; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D011499:Protein Processing, Post-Translational / Q000502:physiology; D000091042:Reelin Protein; D012697:Serine Endopeptidases / Q000172:deficiency
D015816:Cell Adhesion Molecules, Neuronal; C103773:Dab1 protein, mouse; D016326:Extracellular Matrix Proteins; D009419:Nerve Tissue Proteins; D000091042:Reelin Protein; D049452:Green Fluorescent Proteins; D012697:Serine Endopeptidases