2003 Fiscal Year Final Research Report Summary
Migration pathways and fate determination of progenitors in the subventricular zone
| Project/Area Number |
14580767
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Neuroscience in general
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| Research Institution | NIIGATA UNIVERSITY |
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Principal Investigator |
KAKITA Akiyoshi NIIGATA UNIVERSITY, Brain Research Institute, Professor, 脳研究所, 助教授 (80281012)
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| Co-Investigator(Kenkyū-buntansha) |
山田 光則 新潟大学, 脳研究所, 助教授 (30240039)
TAKAHASHI Hitoshi NIIGATA UNIVERSITY, Brain Research Institute, Professor, 脳研究所, 教授 (90206839)
KAKITA Akiyoshi NIIGATA UNIVERSITY, Brain Research Institute, Associate Professor (80281012)
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| Project Period (FY) |
2002 – 2003
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| Keywords | Glial progenitor / Neuronal progenitor / Fate determination / Retrovirus / Fluorescent molecule / Migratory behavior / Brain stem cells / Subventricular zone |
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| Research Abstract |
The great majority of glial cells of the mammalian forebrain are generated in the perinatal period from progenitors in the subventricular zone(SVZ). We investigated the migration of progenitors from the neonatal(postnatal day O,PO) rat forebrain SVZ by labeling them in vivo with a GFP-retrovirus, and monitoring their movements by time-lapse video microscopy in P3 slices. We identified a small number of progenitors that migrated tangentially within the corpus callosum(CC) and crossed the midline. These retained a relatively uniform morphology : the leading process was extended toward the contralateral side, but showed no process branching or turning away from the migratory direction. Net migration requires the elongation of the leading process and nuclear translocation, and the migrating cells in the CC showed both modes. We confirmed the presence of unmyelihated axon bundles within the P3 CC, but failed to detect any radially directed glial processes(vimentin-or GLAST-immunolabeled fibers) spanning through the CC Confocal images showed a close proximity between neurofilament-immunolabeled axons and the leading process of the GFP-expressing progenitors in the CC. The destination of the callosal fibers was examined by applying Dil to the right cingulum ; the labeled fibers ran throughout the CC and reached the left cingulate and motor areas. The distribution and final fates of the retrovirus-labeled cells were examined in P28 brains. A small proportion of the labeled cells, were found in the contralateral hemisphere, where, as oligodendrocytes and astrocytes, they colonized predominantly the cortex and the underlying white matter of the cingulate and secondary motor areas. The distribution pattern appears to coincide well with the projection direction of the callosal fibers. Thus, glial progenitors migrate across the CC, presumably in conjunction with unmyelinated axons, to colonize the contralateral hemisphere.
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