Marthy Hans -Jürg, Dale Brian
Laboratoire Arago, UA 117 du CNRS, Universitè P. et M. Curie, F-66650, Banyuls-sur-mer, France.
Stazione Zoologica di Napoli, Villa Comunale, I-80121, Naples, Italy.
Rouxs Arch Dev Biol. 1989 Nov;198(4):211-218. doi: 10.1007/BF00375907.
Functional cell-to-cell communicaton pathways were studied in pre-organogenetic squid embryos using the fluorescent dyes Lucifer Yellow-CH (LY) and Fluorescein-isothiocyanate Dextran (FITC-D). LY (M.Wt.450) micro-injected into ectoderm or mes-endoderm cells spread extensively over the embryo, flowing laterally along each germ layer, crossing germ layer boundaries and also the cell-to-yolk syncytium boundary. In contrast, when FITC-D (M.Wt.9000 or 17,500) was micro-injected into ectoderm or mes-endoderm cells, spread was limited to a maximum of 7 cells within the respective germ layer.FITC-D did not cross germ-layers or flow into the yolk syncytium. Our results suggest there are two classes of cell-to-cell communication pathways in the germ-layer stage squid embryo; a ubiquitously distributed junction that is permeable to small molecules and a larger junction that allows the transport of both small molecules and macromolecules upto 17.500 M.Wt. The former pathway, which may correspond to the gap junction, is operative throughout the mitotic cycle, while the latter, possibly a cytoplasmic bridge, is functional while cells are in interphase, but does not allow the transport of large molecules during mitotic activity.
利用荧光染料路西法黄-CH（LY）和异硫氰酸荧光素葡聚糖（FITC-D），对器官发生前的鱿鱼胚胎中的功能性细胞间通讯途径进行了研究。将LY（分子量450）显微注射到外胚层或中-内胚层细胞中后，它会在胚胎中广泛扩散，沿着每个胚层横向流动，穿过胚层边界以及细胞与卵黄合胞体的边界。相比之下，当将FITC-D（分子量9000或17500）显微注射到外胚层或中-内胚层细胞中时，其扩散仅限于各自胚层内最多7个细胞。FITC-D不会穿过胚层或流入卵黄合胞体。我们的结果表明，在胚层阶段的鱿鱼胚胎中存在两类细胞间通讯途径；一种是普遍分布的、对小分子可渗透的连接，另一种是更大的连接，它允许小分子和分子量高达17500的大分子运输。前一种途径可能对应于间隙连接，在整个有丝分裂周期中都起作用，而后一种可能是细胞质桥，在细胞处于间期时起作用，但在有丝分裂活动期间不允许大分子运输。
