DELAMINATION AND DIVISION IN THE DROSOPHILA NEURECTODERM - SPATIOTEMPORAL PATTERN, CYTOSKELETAL DYNAMICS, AND COMMON CONTROL BY NEUROGENIC AND SEGMENT POLARITY GENES
DELAMINATION AND DIVISION IN THE DROSOPHILA NEURECTODERM - SPATIOTEMPORAL PATTERN, CYTOSKELETAL DYNAMICS, AND COMMON CONTROL BY NEUROGENIC AND SEGMENT POLARITY GENES
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DOI：
10.1006/dbio.1994.1269
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发表时间：
1994-10-01
影响因子：
2.7
通讯作者：
LEKVEN, A
中科院分区：
文献类型：
--
作者：
HARTENSTEIN, V;YOUNOSSIHARTENSTEIN, A;LEKVEN, A
细胞骨架的变化发生在分层的前体的外围（在蛹背的微毛类前体）和中枢神经系统（胚胎SI神经母细胞）进行了研究。野生型胚胎的腹侧神经外胚层（VN）的细胞分裂模式进行了分析，使用BrdU掺入和相关的神经母细胞分层的模式。最后，缺陷的VN和神经母细胞分层发生在Notch和无翅突变胚胎的增殖模式进行了描述。结果表明，分层和有丝分裂的模式是密切相关的：分层发生在细胞分裂后立即（在微毛类前体的情况下）或分裂前不久（在神经母细胞的情况下）。此外，在分层的神经元前体中可以看到类似于有丝分裂期间发生的细胞骨架变化。因此，在有丝分裂和分层过程中，离散的顶基部定向微管蛋白束断裂。微丝在整个细胞体周围形成一个致密的、弥散的皮层。微管集中在顶端的中心体。有丝分裂和分层之间的关系是支持的发现，神经原性基因Notch和节极性基因wingless（WG）影响腹侧神经外胚层的增殖和分层。因此，在热休克控制下表达神经原性基因Notch的截断胞质结构域的胚胎中（Struhl等人，1993），所有腹侧神经直肠胚层细胞过早地进入有丝分裂，随后没有神经母细胞分层。在wg功能丧失突变体中，VN中的有丝分裂是不规则的，并且通常被推迟，伴随着神经母细胞分层的时间不规则，并且没有神经母细胞的子集。(C)1994年出版社出版。
Cytoskeletal changes occurring during the delamination of precursors of the peripheral (microchaete precursors in the pupal notum) and central nervous system (embryonic SI neuroblasts) were studied. The pattern of cell division in the ventral neurectoderm (VN) of wild-type embryos was analyzed using BrdU incorporation and correlated to the pattern of neuroblast delamination. Finally, defects in the pattern of proliferation of the VN and neuroblast delamination which occur in Notch and wingless mutant embryos were described. The results indicate that the patterns of delamination and mitosis are closely correlated: delamination occurs either immediately after a cell has divided (in case of microchaete precursors) or shortly before the division (in case of the neuroblasts). In addition, cytoskeletal changes similar to those occurring during mitosis can be seen in delaminating neuronal precursors. Thus, during both mitosis and delamination, the discrete apicobasally oriented microfilament-tubulin bundles break down. Microfilaments form a dense, diffuse cortical layer surrounding the entire cell body. Microtubules are concentrated at the apically located centrosome. The relationship between mitosis and delamination is supported by the finding that the neurogenic gene Notch and segment polarity gene wingless (wg) affect both proliferation and delamination in the ventral neurectoderm. Thus, in embryos expressing the trunkated cytoplasmic domain of the neurogenic gene Notch under heat-shock control (Struhl et al., 1993), all ventral neurectodermal cells go into mitosis prematurely, followed by the absence of neuroblast delamination. In wg loss-of-function mutants, mitosis in the VN is irregular and generally postponed, accompanied by irregularities in the timing of neuroblast delamination in general and the absence of a subset of neuroblasts. (C) 1994 Academic Press, Inc.