CRYPTDIN EFFECTS ON CRYPT EPITHELIA

隐形蛋白是一种释放到肠道隐窝腔内的防御素。 由特殊的上皮细胞，如潘氏细胞。这些分子 表现出抗菌活性，因此可能参与保护 隐窝上皮表面，也许是为了防御肠道 一般为上皮表面。我们生成的试点数据表明 这些分子可以通过与隐窝顶膜相互作用， 改变隐窝上皮单层的电生理特性。 特异地提纯的隐蛋白诱导离子的净电传递 穿过这个与根尖引入相关的上皮 频道。这些数据特别令人感兴趣，因为已知 其他种类的防御素分子可以在体内产生阴离子选择性毛孔 人造薄膜。手头的数据与加密最一致 诱导电生的C1转运--一种保护粘膜的事件 用等渗液“冲洗”表面。在这个项目中，我们 将首先描述由以下因素刺激的交通事件的性质 加密密码。其次，我们将使用隐窝上皮单分子层 渗透性基底侧膜，以更好地表征 隐球蛋白引起的毛孔。第三，我们将检查分数 从纯化的加密素物种中提取，以鉴定特定的 隐匿蛋白组分中对隐窝影响的分子(S) 上皮细胞。最后，我们将使用合成肽来验证 负责这些对上皮运输的影响的肽(S)种类 然后合成突变的多肽物种来执行结构功能 分析。这样的数据应该能提供对两国之间的串扰的见解 Paneth细胞和其他隐窝细胞并产生关于如何 这些细胞类型相互作用，以防御地穴单位。

Cryptdins are a form of defensin released into the intestinal crypt lumen by specialized epithelial cells such as Paneth cells. These molecules exhibit antimicrobial activity and thus likely participate in defense of the crypt epithelial surface and perhaps in defense of the intestinal epithelial surface in general. We have generated pilot data indicating that these molecules can, by interacting with crypt apical membranes, alter the electrophysiological properties of crypt epithelial monolayers. Specifically purified cryptdin induces net electrogenic transport of ions across this epithelium associated with the introduction of an apical channel. These data are of particular interest since it is known that other species of defensin molecules can produce anion selective pores in artificial membranes. The data in hand are most consistent with cryptdin induction of electrogenic C1 transport- an event which protects mucosal surfaces by "flushing" them with isotonic solution. In this project we will first characterize the nature of the transport event stimulated by cryptdins. Secondly, we will then use crypt epithelial monolayers with permeabilized basolateral membranes to better characterize the nature of the pore induced by cryptdins. Thirdly, we will examine fractions derived from purified cryptdin species in order to identify the specific molecule(s) in the crytdin fraction responsible for the effects on crypt epithelia. Lastly, we will use synthetic peptides to verify the peptide(s) species responsible for these effects on epithelial transport and then synthesize mutant peptide species to perform structure-function analyses. Such data should provide insights into cross-talk between Paneth cells and other crypt cells and yield information concerning how these cell type interact in defense to the crypt unit.