Determination Mechanism of Organization Center for Pattern Formation in Palleal Buds of Ascidians

海鞘壳芽图案形成组织中心的确定机制

基本信息

批准号：
63540576
负责人：
KAWAMURA Kazuo
金额：
$ 1.34万
依托单位：
Kochi University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1990
项目状态：
已结题

项目摘要

In earlier works of this project, I found that the gut domain is an organization center for antero-posterior pattern formation of a palleal bud in polystyelid ascidians such as Polyzoa and Polyandrocarpa. The organization center was characterized by the aggregation and epithe ial transformation of totipotent stem cells, hemoblasts, and by their entrance into quick cell cycling (Tc=12.5hr). Recently, we have purified a calcium-dependent galactosebinding 14kDa lectin (TC-14) from P. misakiensis, and determined its amino acid sequence. The lectin labeled with FITC or biotin stained hemoblasts. Anti TC-14 polyclonal antibody reacted with the extracellular matrix (ECM) that appeared in the organization center at the earliest stage of bud development. It blocked hemoblasts to differentiate into the gastric epithelium. The results strongly suggested that lectin-positive ECM plays a role in aggregation of hemoblasts toward the epithelium. After western blotting of Polyandrocarpa crude extracts … More on SDS-PAGE, TC-14 showed an affinity for 20kDa polypeptide that was a subunit of 64kDa glycoprotein (GP-64). This reaction required Ca^<2+>, showing that GP-64 is an in vivo target molecule of TC-14. TC-14 had a growthinhibitory effect on hemoblasts in in vivo and in vitro bioassays, whereas GP-64 enhanced their in vivtro proliferation rem arkably. These results strongly suggested that molecular interactions between TC-14 and GP-64 play a key role in totipotency, cell growth and epithelial transformation of hemoblasts at the organization center.I also studied non-peptide effector molecules, of which Prostaglandins (PGs) were found to be involved in exocytosis of lectin granules included in epithelial cells. PGH synthetase was found serologically in blood cells in the vicinity of organization center. Indomethacin, a specific inhibitor of PGs biosynthesis, blocked the exocytosis of lectin granules. The effect of indomethacin was canceled in part by PGs and the organization center reappeared. It is concluded that the determination of organization center in palleal buds involves the spatio-temporal integration of exocytosis of various functional molecules such as TC-14 and GP-64. Less

在该项目的较早作品中，我发现肠道域是一个组织中心的组织中心，用于在多层甲状腺囊体（例如Polyzoa和Polyandrocarpa）中palleal芽形成。该组织中心的特征在于，整整一个干细胞，血红细胞的聚集和上皮转化，并进入快速细胞循环（TC = 12.5hr）。最近，我们纯化了来自Misakiensis的钙依赖性半乳糖糖插入14KDA讲座（TC-14），并确定其氨基酸序列。用FITC或生物素染色的血红蛋白标记的讲座。抗TC-14多克隆抗体与芽发育最早出现在组织中心出现的细胞外基质（ECM）反应。它阻断了血红细胞以区分胃皮细胞。结果强烈表明，讲座阳性的ECM在朝向上皮的血细胞聚集中起作用。在蛋白质的蛋白质印迹polyandrocarpa原油提取物…有关SDS-PAGE的更多信息后，TC-14对20kDa多肽的亲和力显示为64KDA糖蛋白的亚基（GP-64）。该反应需要Ca^<2+>，表明GP-64是TC-14的体内靶标分子。 TC-14对体内和体外生物测定的血小细胞具有生长抑制作用，而GP-64则增强了它们的体内增殖REM。 These results strongly suggested that molecular interactions between TC-14 and GP-64 play a key role in totipotency, cell growth and epithelial transformation of hemoblasts at the organization center.I also studied non-peptide effector molecules, of which Prostaglandins (PGs) were found to be involved in exocytosis of lecture granules included in epithelial cells.在组织中心附近的血细胞中发现了PGH合成酶。 PGS生物合成的特异性抑制剂吲哚美辛阻止了讲座颗粒的胞吐作用。吲哚美辛的作用部分被PGS取消，组织中心重新出现。得出的结论是，palleal芽中组织中心的确定涉及各种功能分子（例如TC-14和GP-64）的胞外增生的空间整合。较少的