CA2+ TRANSPORT FUNCTION OF CHORIOALLANTOIC MEMBRANE

本应用程序的总体目标是了解规则 对胚胎钙代谢的研究，特别强调 经胎盘的钙转运。为建议的 研究了鸡胚绒毛尿囊膜(CAM) 代表相当于禽类胎盘单位的单位，负责 将蛋壳钙转移到胚胎循环中 在开发过程中。本建议书中描述的项目旨在 阐明生化、细胞和分子调控机制 钙调素的钙转运功能。我们的方法是研究 运输相关蛋白(例如，钙结合蛋白，CABP；和 Ca~(2+)-ATPase)是本实验室以前确定的功能标记 钙转运过程中的分子。具体地说，我们计划 首先，在亚细胞级别表征和定位这些组件 分析它们在钙调素中的功能参与和机制作用(S) 运输。其次，我们将研究细胞，生化和 在正常情况下导致CABP表达调控的分子事件 胚胎发育和在实验诱导条件下 维生素K和/或钙缺乏。我们相信这些实验 这里提出的将定义这些标记分子在 钙调素钙转运机制的基础信息 调节一种重要的生理功能--胎盘钙 发育中的脊椎动物胚胎的运输。

The overall objective of this application is to understand the regulation of embryonic calcium metabolism with specific emphasis on the process of transplacental calcium transport. The system chosen for the proposed studies is the chick embryonic chorioallantoic membrane (CAM) which represents the avian equivalent of the placental unit and is responsible for the translocation of eggshell calcium into the embryonic circulation during development. The projects described in this proposal aim to elucidate the biochemical, cellular, and molecular mechanisms regulating the CAM calcium transport function. Our approach is to study the transport-associated proteins (e.g. calcium-binding protein, CaBP; and Ca2+-ATPase) previously identified in this laboratory as functional marker molecules for the calcium transport process. Specifically, we plan to first characterize and localize at a subcellular level these components and analyze their functional involvement and mechanistic role(s) in CAM calcium transport. Secondly, we will study the cellular, biochemical, and molecular events leading to the regulation of CaBP expression during normal embryonic development and under experimentally induced conditions of vitamin K and/or calcium deficiency. We believe that the experiments proposed here will define the functional roles of these marker molecules in CAM calcium transport and provide fundamental information on the mechanisms regulating an important physiological function, transplacental calcium transport, of the developing vertebrate embryo.