Development and analysis of secretory component disrupted mouse

分泌成分(SC)，通常被称为聚合免疫球蛋白受体(PIgR)，是SIgA的一种成分，在粘膜防御系统中发挥重要作用。SC是一种聚合物免疫球蛋白受体，定位于粘膜部位上皮细胞的基侧膜上。因此，它通过上皮细胞将聚合的免疫球蛋白和免疫复合体输送到分泌物中。SC是一种跨膜蛋白，分子量为80 kDa，揭示了1个外显子，由胞外区、跨膜区和胞浆尾部组成。本项目的目的是建立SC干扰小鼠，以检测SC的功能。结果如下：1)用小鼠pIgR基因筛选SC的基因组DNA，并对阳性克隆进行测序。限制性内切酶图谱和Southern杂交结果显示，这些克隆的大小为9.4kb。测序结果表明，BamHI-EcoR I片段全长8404bp，外显子4、5、6、7、8、9、10分别为653、5、6、7、8、9、332、192、129、131和58 bp。内含子4、5、6、7、8、9、10分别为1237bp、552bp891bp、359bp368bp、1106bp101010bp。外显子11至EcoR I片段大小为2543bp。

Secretory component (SC), often called polymeric immunoglobulin receptor (pIgR), is a component of SIgA which plays an important role in the mucosal defense system. SC which is localized on the basolateral membrane of the epithelial cells at the mucosal site is a receptor for polymeric immunoglobulins. Accordingly, it transports polymeric immunoglobulin and immune complex through epithelial cells into the secretion. SC is a transmembrane protein with an Mr of 80 kDa abd cDNA revealed 1 lexons composed of extracellular region, transmembrane region and cytoplasmic tail.The purpose of this project is to develop SC disrupted mouse to examine the function of SC.The results obtained were as follows;1) genomic DNA for SC was screened using a mouse pIgR cDNA and was determined by sequencing of positive clones.2) Five positive clones were obtained. The results of restriction enzyme map and Southern blotting revealed a 9.4 kb of these clones. Sequencing analysis indicated that the BamH I-EcoR I fragment was 8404bp, and exon 4, 5, 6, 7, 8, 9, 10 were 653 bp, 352 bp, 332 bp, 192 bp, 129 bp, 131 bp and 58 bp, respectively. Introns 4, 5, 6, 7, 8, 9, 10 were 1237 bp, 552 bp, 891 bp, 359 bp, 368 bp, 1106 bp and 1010 bp, respectively. The size of the exon 11 to EcoR I fragment was 2543 bp.