Investigation on migration mechanisms of glial progenitors: observations of living cells labeled by dual fluorescent molecules

胶质祖细胞迁移机制的研究：双荧光分子标记活细胞的观察

基本信息

批准号：
12680770
负责人：
KAKITA Akiyoshi
金额：
$ 2.3万
依托单位：
Niigata University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

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 0, 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 unmyelinated axon bundles within the P3 CC, but failed to detect any radially directed glial processes (vimentin- or GLAST-immunolabeled fibers) spanning through the CC. The destination of the callosal fibers was examined by applying DiI 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, less than 1%, 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.

哺乳动物前脑的绝大部分神经胶质细胞是在室内室内（SVZ）的祖细胞中产生的。我们通过用GFP-逆转录病毒在体内标记了新生儿（产后第0天，PO）大鼠前脑SVZ的祖细胞的迁移，并通过P3切片中的P3切片中的延时视频显微镜来监测其运动。我们确定了少数祖细胞在call体（CC）内切向迁移并越过中线。这些保留了相对均匀的形态：领先过程向对侧侧扩展，但没有显示过程分支或远离迁移方向的过程。净迁移需要伸长主要过程和核易位，并且CC中的迁移细胞均显示出两种模式。我们证实了P3 CC内存在不髓鞘的轴突束，但未能检测到跨越CC的任何径向定向的神经胶质过程（波形蛋白或胶形 - 不含纤维状纤维纤维）。通过将DII应用于右扣带，检查了Callos纤维的目的地；标记的纤维贯穿整个CC，并到达左扣带动区和运动区域。在P28大脑中检查了逆转录病毒标记细胞的分布和最终命运。在对侧半球中发现了一小部分标记的细胞，小于1％，在那里，作为少突胶质细胞和星形胶质细胞，它们主要在依赖的皮层和依次和次要运动区域的白质中定居。分布模式似乎与Callosal纤维的投影方向很好地吻合。因此，神经胶质祖细胞跨CC迁移，大概与不髓鞘的轴突结合起来，以定居于对侧半球。