MEDIOLATERAL CELL INTERCALATION IN THE DORSAL, AXIAL MESODERM OF XENOPUS-LAEVIS
MEDIOLATERAL CELL INTERCALATION IN THE DORSAL, AXIAL MESODERM OF XENOPUS-LAEVIS
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DOI：
10.1016/s0012-1606(89)80024-7
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发表时间：
1989-02-01
影响因子：
2.7
通讯作者：
TIBBETTS, P
中科院分区：
文献类型：
--
作者：
KELLER, R;TIBBETTS, P
用荧光素葡聚糖胺（FDA）标记的细胞示踪方法研究了非洲爪蟾原肠胚形成和神经发育过程中中外侧细胞嵌入中胚层组织的模式。将单细胞期注射FDA标记的早期原肠胚闭合边缘区（IMZ）斑块移植到未标记的寄主胚胎的相应区域。将宿主胚胎固定在几个阶段，连续切片，用荧光显微镜和三维重建检查。标记细胞和未标记细胞的混合模式表明，中胚层后部、背侧发生中外侧细胞嵌入，该区域经过会聚延伸并分化为体索和脊索。相反，它不发生在中胚层地幔前前缘的任何背腹部。这些结果与其他证据一起表明，非洲爪蟾的中胚层由两个亚种群组成，每个亚种群都有其独特的形态发生运动、细胞行为和组织命运。迁移的中胚层(1)没有收敛延伸；(2)在囊胚顶迁移扩散；(3)其形态形成依赖于这种基质；(4)中外侧嵌套少；(5)由中胚层地幔的前部、早期受累区域组成；(6)分为头、心、血岛和侧壁中胚层。扩展的中胚层(1)呈收敛扩展；(2)在形态发生上不依赖于囊胚顶；(3)显示广泛的中外侧嵌套；(4)由中胚层地幔的后、后渐开式部分组成；(5)分化为体索和脊索。
The pattern of mediolateral cell intercalation in mesodermal tissues during gastrulation and neurulation of Xenopus laevis was determined by tracing cells labeled with fluorescein dextran amine (FDA). Patches of the involuting marginal zone (IMZ) of early gastrula stage embryos, labeled by injection of FDA at the one-cell stage, were grafted to the corresponding regions of unlabeled host embryos. The host embryos were fixed at several stages, serially sectioned, and examined with fluorescence microscopy and three-dimensional reconstruction. Patterns of mixing of labeled and unlabeled cells show that mediolateral cell intercalation occurs in the posterior, dorsal mesoderm as this region undergoes convergent extension and differentiates into somites and notochord. In contrast, it does not occur in any dorsoventral sector of the anterior, leading edge of the mesodermal mantle. These results, taken with other evidence, suggest that the mesoderm of Xenopus consists of two subpopulations, each with a characteristic morphogenetic movement, cell behavior, and tissue fate. The migrating mesoderm (1) does not show convergent extension; (2) migrates and spreads on the blastocoel roof; (3) is dependent on this substratum for its morphogenesis; (4) shows little mediolateral intercalation; (5) consists of the anterior, early-involving region of the mesodermal mantle; and (6) differentiates into head, heart, blood island, and lateral body wall mesoderm. The extending mesoderm (1) shows convergent extension; (2) is independent of the blastocoel roof in its morphogenesis; (3) show extensive mediolateral intercalation; (4) consists of the posterior, late-involuting parts of the mesodermal mantle; and (5) differentiates into somite and notochord.