碱性磷酸酶在文昌鱼胚胎和幼体中表达图式的研究(英文)

研究组织特异性酶在胚胎发育中的表达图式对于研究细胞、组织和器官的分化具有重要意义。本文以 ＢＣＩＰ为底物研究了碱性磷酸酶在文昌鱼胚胎和幼体中的表达图式。在囊胚、原肠胚和神经胚早期（１２～１３小时）未检测到碱性磷酸酶的特异性表达；到神经胚中期（１５小时，约６个体节），碱性磷酸酶在胚胎每一体节的中部开始表达，在胚胎中形成３～６个条纹（Ｆｉｇ．１）；在１８小时神经胚（９～１０体节）中，碱性磷酸酶在肌节中表达（Ｆｉｇ．２）；到２４小时在后部内胚层中也开始表达（Ｆｉｇ．３）；在３６～４８小时幼体中，碱性磷酸酶在消化道中强烈表达，但在咽鳃区不表达，同时在肌节中仍有弱的表达（Ｆｉｇ．４）。研究表明碱性磷酸酶可能在肌节的发育过程中具有一定作用。碱性磷酸酶在消化道中的表达可能与这一时期消化道开始行使功能有关。另外，Ｌ－苯丙氨酸只抑制３６、４８小时文昌鱼肠碱性磷酸酶活性，不抑制其体节肠碱性磷酸酶活性（Ｆｉｇ．５）、表明文昌鱼至少存在两种碱性磷酸酶：在消化道中表达的是一种肠型的，与脊椎动物碱性磷酸酶可能为同一类型；另一种主要在肌节中表达，可能是组织非特异性的破性磷酸酶。以上结果说明文昌鱼早期发育中碱性磷酸酶的表达与脊椎动物相似，具

Expression Pattern of Alkaline Phosphatase in Amphioxus Embryo and Larva

Alkaline phosphatase (AP) activity is stage and tissue specific in Amphioxus embryo and larva. By histochemical staining, no Ap activity was detected in Amphioxus embryos when they were younger than 15 h. Ap activity appeared in the somites of 15-h embryo and was highest in somites 3-5. During later development, the expression of Ap persisted in the myotomes till at least the 48-h stage. AP began to appear in the posterior endoderm of 24-h larvae. In 36-48 h larvae, AP was expressed strongly in the whole endoderm except the pharyngeal region. By the inhibitory effect of phenylalanine on AP expression, there are two kinds of Aps expressed in the Amphioxus endoderm and myotome. The endodermal Ap was apparently of intestinal type and the myotomal AP was probably of non-tissue-specific type.